- Email: [email protected]
classical galactosemia genetic compound
Volume 94 Number 6
B r i e f clinical and laboratory observations
lism. Retrospectively, a dietary history revealed the patient's favorite foods to be eggs, fish of any kind but particularly tuna fish, liver, and vegetables from the legume family. Laboratory data revealed normal serum and urine amino acid values. A spot urine obtained after one of his "favorite meals," a tuna fish sandwich (egg included) and a large portion of English peas, was examined for urinary volatiles by a method described by Lee et al. '-'-4A large peak was observed during gas chromatography and was accompanied by an odor described as that of putrid fish. The volatile substance was identified as trimethylamine, as it occurred at its molecular weight of 59. As a result of the gas chromatography study, the patient was begun on a diet low in choline (no eggs, fish, liver, or legumes). After one week of dietary management, a spot urine examination revealed only a trace of trimethylamine. A follow-up one year after the diet was begun revealed no problem with the odor. The young man also had a near straight "A" average in the ninth grade, was dating, and had made many friends. No further signs or symptoms of depression were noted by the parents. DISCUSSION In 1970 Humbert et al:' described a 6-year-old girl with a recurrent fishy odor and elevated amounts of trimethylamine in her urine. A liver biopsy was performed on this patient and a deficiency in liver trimethylamine oxidase was reported. This patient was described as having the clinical features of N o o n a n syndrome; this association has also been reported by Calvert." In 1976 three other patients with trimethylaminuria, ages 6 years, 3 months, and 3 months, were described by Lee et al. 2 In the older child the odor followed the ingestion of fish; in the two younger patients the odor occurred after the ingestion of milk from their mother, who had eaten either fish or eggs before breast feeding. All children were described as developing normally on follow-up examinations years later. Although trimethylamine is a normal volatile urine constituent, the presence of a large peak with an accompanying putrid fish odor strongly suggests a defect in
93 7
trimethylamine metabolism. The metabolic degradation of trimethylamine has been well described by Higgins et al 7 and by de la Huerga and Popper) and need not be discussed in this paper. Although the majority of case reports described children with normal intelligence and physical growth, only one mention is made of the social stigma associated with this disease.-' Our patient clearly had as the major manifestation of his disease psychosocial problems of a significant degree. What was most rewarding in this patient was the ability to cure a social disease manifested by poor school performance, aggressive behavior, and symptoms and signs suggestive of an adolescent depressive reaction by simple dietary restrictions. REFERENCES
1. Mace JW, Goodman SI, Centerwall WR, and Chinnock RF: The child with an unusual odor, Clin Pediatr 15:57, 1976. 2. Lee CWG, Yu TS, Turner BB, and Murray KE: Trimethylaminuria: Fishy odors in children, N Engl J Med 295:937, 1976. 3. Murray KE, Shipton J, and Whitefield FB: The chemistry of food flavor: I. Volatile constituents of passionfruit, Passiflora edulis, Aust J Chem 25:1921, 1972. 4. Matsumoto KE, Partridge DH, Robinson AB, Pauling L, Flath RA, Mon PR, and Teranishi R: The identification of volatile compounds in human urine, J Chromatogr 85:3l, 1973. 5. Humbert JR, Hammond KB, Hathaway WE, Marcoux JG, and O'Brien D: Trimethylaminuria: The fish odor syndrome, Lancet 2:770, 1970. 6. Calvert GD: Trimethylaminuria and inherited Noonan's syndrome, Lancet 1:320, 1973. 7. Higgins T, Chayvin S, Hammond KB, and Humbert JR: Trimethylamine N-oxide synthesis: A human variant, Biochem Med 6:392, 1972. 8. de la Huerga J, and Popper H: Urine excretion of choline metabolites following choline administration in normals and patients with hepatobiliary diseases, J Clin Invest 30:463, 1951.
Significance of the Duarte/classical galactosemia genetic compound Sally Kelly, Ph.D., M.D., Albany, N. Y.
From the New York State Department of Health, Birth Defects Institute, Division of Laboratories & Research. Reprint address: New York State Department of Health, Birth Defects Institute, Division of Laboratories & Research, Empire State Plaza, Tower Bldg., Albany, NY 12201.
0022-3476/79/600937 + 04500.40/0 9 1979 The C. V. Mosby Co.
NEWBORN INFANTS in many parts of the world are now screened for galactosemia by means of a fluorescent spot test? The test indicates the presence or absence of galactose-l-phosphate uridyl transferase in blood, and was designed to identify infants with a complete deficiency of
93 8
Brief clinical and laboratory observations
the enzyme i.e., the biochemical phenotype of classical galactosemia. Occasionally the test may reveal the low transferase activities found in carriers of classical galactosemia and in infants with genes for electrophoretic variants of the transferase, such as the Duarte variant. I-:~ Infants with two mutant genes, a gene for the Duarte variant transferase and an allele for galactosemia, referred to here as the Duarte/galactosemia genetic compound (GtD/gt), are especially likely to have positive screening tests, with lower erythrocyte transferase activities than in carriers of classical galactosemia or in individuals with the Duarte gene only. There is uncertainty whether these infants should be singled out for further study and, perhaps, dietary treatment. Levy et aP have assembled evidence suggesting that the genetic compound is probably benign "in any known combination." We have evidence from ten individuals which suggests, on the other hand, that the genetic compound early in life may not be entirely benign. MATERIALS
AND METHODS
Our ten subjects with the Duarte/galactosemia genetic compound included seven infants with low activities of erythrocyte ga!actose-l-phosphate uridyl transferase discovered through newborn screening programs carried out by the New York State Department of Health's Division of Laboratories and Research (Albany), the Erie County Health Department Laboratory (Buffalo), and the New York City Health Department Laboratory. The three other individuals with the compound genotype were adults found through family studies, two of whom were the parents of infants identified through the screening program and were found to have classical galactosemia or the phenotype of the galactosemia carrier. The third was the mother of two children with galactosemia; her son died as a newborn infant with clinical and postmortem findings of galactosemia, but a daughter born during our study has been treated since birth. The low transferase activities in the newborn infants were initially detected in fluorescent spot tests I of dried blood on filter paper. Transferase activities were measured in heparinized blood from the infants and their relatives by a fluorimetric method.~ Electrophoretic mobilities of erythrocyte transferase on starch gels were determined by Ng et al's method? Phen0types in the parents and other close relatives were tentatively assigned from the transferase activities and were finally assigned after interpretation of the electrophoretic patterns. Transferase activities in carriers of classical galactosemia and Duarte homozygous persons are about half that of normal persons (a range of from 19
The Journal of Pediatrics Jane 1979
to 29 units/gm hemoglobin in our laboratory). Carriers of the Duarte variant have about three-fourths normal activity, and individuals with the Duarte/galactosemia genetic compound have considerably less activity than carriers of classical gatactosemia. In our experience, infants with classical galactosemia have no transferase activity. Individuals homozygous for the Duarte variant (GtD/Gt D) have an electrophoretic pattern consisting of a single band with greater mobility than the single band of transferase found in normal subjects or in persons heterozygous for galactosemi a. The pattern from the Duarte/ normal heterozygous person consists of both the Duarte and normal transferase bands, and the Duarte/galactosemia genetic compound displays only the Duarte transferase band. RESULTS Erythrocyte transferase in the seven newborn infants with the genetic compound appeared absent in the spot tests performed by the screening laboratories; the spots were nonfluorescing, i.e., were "black," in contrast to "bright," "dull," or "very dull" spots, and were not distinguishable from those given by infants with classical galactosemia. Transferase activity in the whole blood samples from the newborn ~nfants with the Duarte/galactosemia genetic compound ranged from < 1.0 to 3.6 U/gm Hgb with a mean of 2.4 U/gm Hgb, compared to normal values of from 19 to 29 U/gm Hgb. Erythrocyte transferase activities in the three adults were 4.5, 6.9, and 3.4 U/gm Hgb, respectively, with a mean of 4.9 U/gin Hgb. Electrophoretic patterns of the transferase in hemolysates from the three, adults and five of the infants consisted of a single fast-moving band, characteristic of the Duarte variant enzyme. C-1 and J's electrophoretic patterns were not discernible during the first several months of life, when their erythrocyte transferase levels remained very low. The inheritance of the genetic compound was traced through studies of the transferase phenotypes in the obligate carriers (parents and/or offspring), when available, and in other close relatives. Transferase phenotypes of the carrier of classical galactosemia (Gv/gt) were assigned in 11 subjects with transferase activities ranging from 6.2 to 16 U/gm Hgb, with a mean of 9.5 U/gm Hgb, and with the electrophoretic mobility of normal transferase. Two subjects had the phenotype of the Duarte variant homozygote, with activities of 9.8 and 8.1 U/gm Hgb and electrophoretic mobility of the Duarte band only. Seven individuals had the phenotype of the Duarte variant carrier (GtD/GtO, with activities of from 10 to 19 U/gm
Volume 94 Number 6
Hgb and a mean of 14 U/gm Hgb, and electrophoretic patterns of both Duarte and normal transferase. In five families in which both parents were tested (B, C, D, E, H), the Duarte gene (Gt D) was expressed by one parent and the gene for galactosem!a (gt) by the other (Table). In the A and J families, in which only one parent could be tested, the mothers had phenotypes of the Duarte carrier and Duarte homozygote, respectively. In the F and H families, the infants had classical galactosemia and the respective mothers had th e Duarte/galactosemia genetic compound; in the H family, the galactosemia gene was traced through four generations. In the G family, the newborn infant's phenotype was that of a carrier of classical galactosemia, and the father had the Duarte/ galactosemia genetic compound. (Detailed information is available upon request.) Clinical signs suggestive of galactosemia appeared in one newborn infant with the Duart e/galactosemia genetic compound. The infant in family E, whose mother had sepsis before delivery, developed jaundice, hepatomegaly, and lethargy a few days after birth, and was given a galactose-free diet. His blood galactose levels were normal, however, when challenged with galactosecontaining formula several months later, after which he was given a regular formula. Abnormal metabolities of galactosemia were found in the blood of three other newborn infants with the Duarte/ galactosemia genetic compound after several days of milk feeding. Infant B's blood contained about 40 mg galactose/dl and 9 mg galactose-l-phosphate/dl, infant D's blood contained 18 mg galactose/dl, and infant J's blood contained from 30 to 60 mg galactose/dl. The three infants were given galactose-free diets when one (B, D) or two weeks (J) of age. Transferase activity in C-l's erythrocytes was so low during the newborn period, i.e., undetectable on several occasions, that she was given a galactose-free diet when one month of age. By 15 months, however, her erythrocyte transferase activity (5 U/g Hgb) was similar to that of other subjects with the Duarte/galactosemia genetic compound. The younger sister, C-2, whose erythrocyte transferase activity was 6 U/g Hgb when one month of age, was given a galactose-free diet soon after birth because of her abnormal screening test and the sister's history. The seventh infant, A, remained well on milk feedings, had no detectable blood galactose, and was not treated. Although the adults with the genetic compound were not examined for long-term effects of galactosemia, e.g., evidence of cataract formation by slit-lamp examination, they are, for the most part, healthy. One, a mother (family
Brief clinical and laboratory observations
939
Table. Genotypes predicted for obligate carrier relatives of patients with the Duarte/galactosemia genetic compound (Gtt'/gt) Predicted genotype (family) Relative
Gt +/gt
Father Mother Offspring
B,D,E.H C F,G
C
A,B,E,H F
D,J F,H
H), is athletic; as an infant, however, she had had colic, and now has allergies, intolerance to milk, and asthma. Her two brothers, one of whom has biochemical characteristics of a Duarte carrier, were healthy as infants. Another mother, educated in "special" classes, is a construction worker. The third adult is a father whose medical history is unremarkable. DISCUSSION Our data are not entirely in accord with Levy et al's 4 findings, which led them to conclude that the Duarte/ galactosemia genetic compound "in any known combination is probably benign." Clinical signs in one infant and biochemical indices in four others, of seven newborn infants in our study, prompted the respective attending physicians to prescribe galactose-free diets. We are less Certain than Levy et al of the longer-term effects of the genetic compound, however, since all but one of our infants were treated by one month of age. We agree that the genetic compound is relatively benign in most infants and that the decision to treat, if questionable, should be based on the demonstration of abnormal biochemical indices. The fact that six infants remained healthy after several days of milk feedings clearly attests to the relative benignity of the Duarte/galact0semia genetic compound. The clinical signs in one infant and the biochemical abnormalities in others, however, raise the possibility that the genetic compound, on occasion, is not entirely innocuous. We thank the several physicians in New York State who provided us with the patients' histories and samples. REFERENCES
1. Beutler E, and Baiuda MC: A simple spot screening test for galactosemia, J Lab Clin Med 68:137, 1966. 2. Beutler E, Baluda MC, Sturgeon P, and Day R: A new genetic abnormality resulting in galactose-l-phosphate uridyl transferase deficiency, Lancet 1:353, 1965. 3. Kelly S, Desjardins L, Armerding P, and Burns J: Pheno-
940
Brief clinical and laboratory observations
types of galactosemia in infants screened at birth, J Med Gen 10:27, 1973. 4. Levy HL, Sepe SJ, Walton DS, Shih VE, Hammersen G, Houghton S, and Beutler E: Galactose-l-phosphate uridyl transferase deficiency due to Duarte/galactosemia combined variation: Clinical and biochemical studies, J I~DIATR 92:390, 1978. 5. Beutler E, and Mitchell M: New rapid method for estima-
The Journal of Pediatrics June 1979
tion of red cell galactose-l-phosphate uridyl transferase activity, J Lab Clin Med 72:527, 1968. Ng W, Bergren WR, Fields M, and Donnell GN: An improved electrophoretic procedure for galactose-l-phosphate uridyl transferase: demonstration of multiple activity bands with the Duarte variant, Biochem Biophys Res Commun 37:354, 1969.
Qualitative deferoxamine color test for iron ingestion Michael A. MeGuigan, M.D., C.M.,* Frederick H. Lovejoy, Jr., M.D., Susan K. Marian, Richard D. Propper, M.D., and Peter Goldman, M.D., Boston, Mass.
O P T I MAL MAN AG E MEN T of the patient with a recent ingestion requires accurate and rapid identification of the agent. Methods available for identifying iron are generally unsatisfactory. ~ Interpretation of the plain x-ray film of the abdomen is not necessarily accurate, and the determination of serum iron and iron-binding capacity is often associated with a significant time delay and is costly. This report describes a rapid, simple screening test for the presence of iron in the stomach and its utility in evaluating the patient with a possible iron ingestion. METHODS
Deferoxamine color test. Two milligrams of gastric fluid and two drops of 30% H~O,_,are placed in each of two disposable plastic tubes. A solution of deferoxamine is freshly prepared by adding 4 ml of distilled water to one ampule of deferoxamine (500 rag/ampule). One-half milliliter of the deferoxamine solution is then added to the contents of one tube. After mixing, the colors of the contents of the two tubes are compared. If iron is present in the gastric fluid, there will be an immediate change in the color of the tube to which deferoxamine was added. From the Department of Medicine, Hematology and Clinical Pharmacology~Toxicology Unit, The Children's Hospital Medical Center, the Department of Pediatrics and Pharmacology, Harvard Medical School and the Massachusetts Poison Control System. Supported in part by a special award from the Burroughs wellcome fund. Presented in part at the Fall Meeting of the American Academy of Clinical Toxicology and American Association of Poison Control Centers, Chicago, October 1978. *Reprint address: The Children~ Hospital Medical Center, 300 LongwoodA re., Boston. MA 02115.
The color may vary from light orange (with small amounts of iron) to dark red (with large amounts of iron). The tube without deferoxamine will not change color. Since the test is quite sensitive, it is important that laboratory ware be free of iron. Laboratory. Serum iron concentration and iron-binding capacity were determined by the various hospital chemistry laboratories utilizing a colorimetric assay 2 or an auto-analyser technique. Study groups. Test results were compared in the gastric contents of two groups of patients. One consisted of patients who presented between January, 1977, and October, 1977, to the Boston Poison Information Center with a history suggesting the ingestion of an iron-containing medication in the preceding three hours. For each of these patients, the results from one of two tests ordinarily used to confirm the diagnosis of iron ingestion (serum iron determination or plain x-ray film of the abdomen) were obtained. The second group was randomly selected from patients who had presented to the Emergency Room of the Children's Hospital Medical Center during the same period of time with a history of the ingestion of a product not containing iron. Gastric contents were obtained from all patients, either by spontaneous vomiting or after emesis had been induced by syrup of ipecac. RESULTS
Iron compounds. Initial in vitro testing of the deferoxamine color test demonstrated that the addition of iron in various concentrations (from 4.0/~g/ml to 1.0 mg/ml) to gastric fluid produced color changes that ranged from light orange to dark red. The clinical history and test results from 11 patients are summarized in Table I. Patient ages ranged from 11 to 32
0022-3476/79/600940+ 0350030/0 9 1979 The C. V. Mosby Co.
B r i e f clinical and laboratory observations
lism. Retrospectively, a dietary history revealed the patient's favorite foods to be eggs, fish of any kind but particularly tuna fish, liver, and vegetables from the legume family. Laboratory data revealed normal serum and urine amino acid values. A spot urine obtained after one of his "favorite meals," a tuna fish sandwich (egg included) and a large portion of English peas, was examined for urinary volatiles by a method described by Lee et al. '-'-4A large peak was observed during gas chromatography and was accompanied by an odor described as that of putrid fish. The volatile substance was identified as trimethylamine, as it occurred at its molecular weight of 59. As a result of the gas chromatography study, the patient was begun on a diet low in choline (no eggs, fish, liver, or legumes). After one week of dietary management, a spot urine examination revealed only a trace of trimethylamine. A follow-up one year after the diet was begun revealed no problem with the odor. The young man also had a near straight "A" average in the ninth grade, was dating, and had made many friends. No further signs or symptoms of depression were noted by the parents. DISCUSSION In 1970 Humbert et al:' described a 6-year-old girl with a recurrent fishy odor and elevated amounts of trimethylamine in her urine. A liver biopsy was performed on this patient and a deficiency in liver trimethylamine oxidase was reported. This patient was described as having the clinical features of N o o n a n syndrome; this association has also been reported by Calvert." In 1976 three other patients with trimethylaminuria, ages 6 years, 3 months, and 3 months, were described by Lee et al. 2 In the older child the odor followed the ingestion of fish; in the two younger patients the odor occurred after the ingestion of milk from their mother, who had eaten either fish or eggs before breast feeding. All children were described as developing normally on follow-up examinations years later. Although trimethylamine is a normal volatile urine constituent, the presence of a large peak with an accompanying putrid fish odor strongly suggests a defect in
93 7
trimethylamine metabolism. The metabolic degradation of trimethylamine has been well described by Higgins et al 7 and by de la Huerga and Popper) and need not be discussed in this paper. Although the majority of case reports described children with normal intelligence and physical growth, only one mention is made of the social stigma associated with this disease.-' Our patient clearly had as the major manifestation of his disease psychosocial problems of a significant degree. What was most rewarding in this patient was the ability to cure a social disease manifested by poor school performance, aggressive behavior, and symptoms and signs suggestive of an adolescent depressive reaction by simple dietary restrictions. REFERENCES
1. Mace JW, Goodman SI, Centerwall WR, and Chinnock RF: The child with an unusual odor, Clin Pediatr 15:57, 1976. 2. Lee CWG, Yu TS, Turner BB, and Murray KE: Trimethylaminuria: Fishy odors in children, N Engl J Med 295:937, 1976. 3. Murray KE, Shipton J, and Whitefield FB: The chemistry of food flavor: I. Volatile constituents of passionfruit, Passiflora edulis, Aust J Chem 25:1921, 1972. 4. Matsumoto KE, Partridge DH, Robinson AB, Pauling L, Flath RA, Mon PR, and Teranishi R: The identification of volatile compounds in human urine, J Chromatogr 85:3l, 1973. 5. Humbert JR, Hammond KB, Hathaway WE, Marcoux JG, and O'Brien D: Trimethylaminuria: The fish odor syndrome, Lancet 2:770, 1970. 6. Calvert GD: Trimethylaminuria and inherited Noonan's syndrome, Lancet 1:320, 1973. 7. Higgins T, Chayvin S, Hammond KB, and Humbert JR: Trimethylamine N-oxide synthesis: A human variant, Biochem Med 6:392, 1972. 8. de la Huerga J, and Popper H: Urine excretion of choline metabolites following choline administration in normals and patients with hepatobiliary diseases, J Clin Invest 30:463, 1951.
Significance of the Duarte/classical galactosemia genetic compound Sally Kelly, Ph.D., M.D., Albany, N. Y.
From the New York State Department of Health, Birth Defects Institute, Division of Laboratories & Research. Reprint address: New York State Department of Health, Birth Defects Institute, Division of Laboratories & Research, Empire State Plaza, Tower Bldg., Albany, NY 12201.
0022-3476/79/600937 + 04500.40/0 9 1979 The C. V. Mosby Co.
NEWBORN INFANTS in many parts of the world are now screened for galactosemia by means of a fluorescent spot test? The test indicates the presence or absence of galactose-l-phosphate uridyl transferase in blood, and was designed to identify infants with a complete deficiency of
93 8
Brief clinical and laboratory observations
the enzyme i.e., the biochemical phenotype of classical galactosemia. Occasionally the test may reveal the low transferase activities found in carriers of classical galactosemia and in infants with genes for electrophoretic variants of the transferase, such as the Duarte variant. I-:~ Infants with two mutant genes, a gene for the Duarte variant transferase and an allele for galactosemia, referred to here as the Duarte/galactosemia genetic compound (GtD/gt), are especially likely to have positive screening tests, with lower erythrocyte transferase activities than in carriers of classical galactosemia or in individuals with the Duarte gene only. There is uncertainty whether these infants should be singled out for further study and, perhaps, dietary treatment. Levy et aP have assembled evidence suggesting that the genetic compound is probably benign "in any known combination." We have evidence from ten individuals which suggests, on the other hand, that the genetic compound early in life may not be entirely benign. MATERIALS
AND METHODS
Our ten subjects with the Duarte/galactosemia genetic compound included seven infants with low activities of erythrocyte ga!actose-l-phosphate uridyl transferase discovered through newborn screening programs carried out by the New York State Department of Health's Division of Laboratories and Research (Albany), the Erie County Health Department Laboratory (Buffalo), and the New York City Health Department Laboratory. The three other individuals with the compound genotype were adults found through family studies, two of whom were the parents of infants identified through the screening program and were found to have classical galactosemia or the phenotype of the galactosemia carrier. The third was the mother of two children with galactosemia; her son died as a newborn infant with clinical and postmortem findings of galactosemia, but a daughter born during our study has been treated since birth. The low transferase activities in the newborn infants were initially detected in fluorescent spot tests I of dried blood on filter paper. Transferase activities were measured in heparinized blood from the infants and their relatives by a fluorimetric method.~ Electrophoretic mobilities of erythrocyte transferase on starch gels were determined by Ng et al's method? Phen0types in the parents and other close relatives were tentatively assigned from the transferase activities and were finally assigned after interpretation of the electrophoretic patterns. Transferase activities in carriers of classical galactosemia and Duarte homozygous persons are about half that of normal persons (a range of from 19
The Journal of Pediatrics Jane 1979
to 29 units/gm hemoglobin in our laboratory). Carriers of the Duarte variant have about three-fourths normal activity, and individuals with the Duarte/galactosemia genetic compound have considerably less activity than carriers of classical gatactosemia. In our experience, infants with classical galactosemia have no transferase activity. Individuals homozygous for the Duarte variant (GtD/Gt D) have an electrophoretic pattern consisting of a single band with greater mobility than the single band of transferase found in normal subjects or in persons heterozygous for galactosemi a. The pattern from the Duarte/ normal heterozygous person consists of both the Duarte and normal transferase bands, and the Duarte/galactosemia genetic compound displays only the Duarte transferase band. RESULTS Erythrocyte transferase in the seven newborn infants with the genetic compound appeared absent in the spot tests performed by the screening laboratories; the spots were nonfluorescing, i.e., were "black," in contrast to "bright," "dull," or "very dull" spots, and were not distinguishable from those given by infants with classical galactosemia. Transferase activity in the whole blood samples from the newborn ~nfants with the Duarte/galactosemia genetic compound ranged from < 1.0 to 3.6 U/gm Hgb with a mean of 2.4 U/gm Hgb, compared to normal values of from 19 to 29 U/gm Hgb. Erythrocyte transferase activities in the three adults were 4.5, 6.9, and 3.4 U/gm Hgb, respectively, with a mean of 4.9 U/gin Hgb. Electrophoretic patterns of the transferase in hemolysates from the three, adults and five of the infants consisted of a single fast-moving band, characteristic of the Duarte variant enzyme. C-1 and J's electrophoretic patterns were not discernible during the first several months of life, when their erythrocyte transferase levels remained very low. The inheritance of the genetic compound was traced through studies of the transferase phenotypes in the obligate carriers (parents and/or offspring), when available, and in other close relatives. Transferase phenotypes of the carrier of classical galactosemia (Gv/gt) were assigned in 11 subjects with transferase activities ranging from 6.2 to 16 U/gm Hgb, with a mean of 9.5 U/gm Hgb, and with the electrophoretic mobility of normal transferase. Two subjects had the phenotype of the Duarte variant homozygote, with activities of 9.8 and 8.1 U/gm Hgb and electrophoretic mobility of the Duarte band only. Seven individuals had the phenotype of the Duarte variant carrier (GtD/GtO, with activities of from 10 to 19 U/gm
Volume 94 Number 6
Hgb and a mean of 14 U/gm Hgb, and electrophoretic patterns of both Duarte and normal transferase. In five families in which both parents were tested (B, C, D, E, H), the Duarte gene (Gt D) was expressed by one parent and the gene for galactosem!a (gt) by the other (Table). In the A and J families, in which only one parent could be tested, the mothers had phenotypes of the Duarte carrier and Duarte homozygote, respectively. In the F and H families, the infants had classical galactosemia and the respective mothers had th e Duarte/galactosemia genetic compound; in the H family, the galactosemia gene was traced through four generations. In the G family, the newborn infant's phenotype was that of a carrier of classical galactosemia, and the father had the Duarte/ galactosemia genetic compound. (Detailed information is available upon request.) Clinical signs suggestive of galactosemia appeared in one newborn infant with the Duart e/galactosemia genetic compound. The infant in family E, whose mother had sepsis before delivery, developed jaundice, hepatomegaly, and lethargy a few days after birth, and was given a galactose-free diet. His blood galactose levels were normal, however, when challenged with galactosecontaining formula several months later, after which he was given a regular formula. Abnormal metabolities of galactosemia were found in the blood of three other newborn infants with the Duarte/ galactosemia genetic compound after several days of milk feeding. Infant B's blood contained about 40 mg galactose/dl and 9 mg galactose-l-phosphate/dl, infant D's blood contained 18 mg galactose/dl, and infant J's blood contained from 30 to 60 mg galactose/dl. The three infants were given galactose-free diets when one (B, D) or two weeks (J) of age. Transferase activity in C-l's erythrocytes was so low during the newborn period, i.e., undetectable on several occasions, that she was given a galactose-free diet when one month of age. By 15 months, however, her erythrocyte transferase activity (5 U/g Hgb) was similar to that of other subjects with the Duarte/galactosemia genetic compound. The younger sister, C-2, whose erythrocyte transferase activity was 6 U/g Hgb when one month of age, was given a galactose-free diet soon after birth because of her abnormal screening test and the sister's history. The seventh infant, A, remained well on milk feedings, had no detectable blood galactose, and was not treated. Although the adults with the genetic compound were not examined for long-term effects of galactosemia, e.g., evidence of cataract formation by slit-lamp examination, they are, for the most part, healthy. One, a mother (family
Brief clinical and laboratory observations
939
Table. Genotypes predicted for obligate carrier relatives of patients with the Duarte/galactosemia genetic compound (Gtt'/gt) Predicted genotype (family) Relative
Gt +/gt
Father Mother Offspring
B,D,E.H C F,G
C
A,B,E,H F
D,J F,H
H), is athletic; as an infant, however, she had had colic, and now has allergies, intolerance to milk, and asthma. Her two brothers, one of whom has biochemical characteristics of a Duarte carrier, were healthy as infants. Another mother, educated in "special" classes, is a construction worker. The third adult is a father whose medical history is unremarkable. DISCUSSION Our data are not entirely in accord with Levy et al's 4 findings, which led them to conclude that the Duarte/ galactosemia genetic compound "in any known combination is probably benign." Clinical signs in one infant and biochemical indices in four others, of seven newborn infants in our study, prompted the respective attending physicians to prescribe galactose-free diets. We are less Certain than Levy et al of the longer-term effects of the genetic compound, however, since all but one of our infants were treated by one month of age. We agree that the genetic compound is relatively benign in most infants and that the decision to treat, if questionable, should be based on the demonstration of abnormal biochemical indices. The fact that six infants remained healthy after several days of milk feedings clearly attests to the relative benignity of the Duarte/galact0semia genetic compound. The clinical signs in one infant and the biochemical abnormalities in others, however, raise the possibility that the genetic compound, on occasion, is not entirely innocuous. We thank the several physicians in New York State who provided us with the patients' histories and samples. REFERENCES
1. Beutler E, and Baiuda MC: A simple spot screening test for galactosemia, J Lab Clin Med 68:137, 1966. 2. Beutler E, Baluda MC, Sturgeon P, and Day R: A new genetic abnormality resulting in galactose-l-phosphate uridyl transferase deficiency, Lancet 1:353, 1965. 3. Kelly S, Desjardins L, Armerding P, and Burns J: Pheno-
940
Brief clinical and laboratory observations
types of galactosemia in infants screened at birth, J Med Gen 10:27, 1973. 4. Levy HL, Sepe SJ, Walton DS, Shih VE, Hammersen G, Houghton S, and Beutler E: Galactose-l-phosphate uridyl transferase deficiency due to Duarte/galactosemia combined variation: Clinical and biochemical studies, J I~DIATR 92:390, 1978. 5. Beutler E, and Mitchell M: New rapid method for estima-
The Journal of Pediatrics June 1979
tion of red cell galactose-l-phosphate uridyl transferase activity, J Lab Clin Med 72:527, 1968. Ng W, Bergren WR, Fields M, and Donnell GN: An improved electrophoretic procedure for galactose-l-phosphate uridyl transferase: demonstration of multiple activity bands with the Duarte variant, Biochem Biophys Res Commun 37:354, 1969.
Qualitative deferoxamine color test for iron ingestion Michael A. MeGuigan, M.D., C.M.,* Frederick H. Lovejoy, Jr., M.D., Susan K. Marian, Richard D. Propper, M.D., and Peter Goldman, M.D., Boston, Mass.
O P T I MAL MAN AG E MEN T of the patient with a recent ingestion requires accurate and rapid identification of the agent. Methods available for identifying iron are generally unsatisfactory. ~ Interpretation of the plain x-ray film of the abdomen is not necessarily accurate, and the determination of serum iron and iron-binding capacity is often associated with a significant time delay and is costly. This report describes a rapid, simple screening test for the presence of iron in the stomach and its utility in evaluating the patient with a possible iron ingestion. METHODS
Deferoxamine color test. Two milligrams of gastric fluid and two drops of 30% H~O,_,are placed in each of two disposable plastic tubes. A solution of deferoxamine is freshly prepared by adding 4 ml of distilled water to one ampule of deferoxamine (500 rag/ampule). One-half milliliter of the deferoxamine solution is then added to the contents of one tube. After mixing, the colors of the contents of the two tubes are compared. If iron is present in the gastric fluid, there will be an immediate change in the color of the tube to which deferoxamine was added. From the Department of Medicine, Hematology and Clinical Pharmacology~Toxicology Unit, The Children's Hospital Medical Center, the Department of Pediatrics and Pharmacology, Harvard Medical School and the Massachusetts Poison Control System. Supported in part by a special award from the Burroughs wellcome fund. Presented in part at the Fall Meeting of the American Academy of Clinical Toxicology and American Association of Poison Control Centers, Chicago, October 1978. *Reprint address: The Children~ Hospital Medical Center, 300 LongwoodA re., Boston. MA 02115.
The color may vary from light orange (with small amounts of iron) to dark red (with large amounts of iron). The tube without deferoxamine will not change color. Since the test is quite sensitive, it is important that laboratory ware be free of iron. Laboratory. Serum iron concentration and iron-binding capacity were determined by the various hospital chemistry laboratories utilizing a colorimetric assay 2 or an auto-analyser technique. Study groups. Test results were compared in the gastric contents of two groups of patients. One consisted of patients who presented between January, 1977, and October, 1977, to the Boston Poison Information Center with a history suggesting the ingestion of an iron-containing medication in the preceding three hours. For each of these patients, the results from one of two tests ordinarily used to confirm the diagnosis of iron ingestion (serum iron determination or plain x-ray film of the abdomen) were obtained. The second group was randomly selected from patients who had presented to the Emergency Room of the Children's Hospital Medical Center during the same period of time with a history of the ingestion of a product not containing iron. Gastric contents were obtained from all patients, either by spontaneous vomiting or after emesis had been induced by syrup of ipecac. RESULTS
Iron compounds. Initial in vitro testing of the deferoxamine color test demonstrated that the addition of iron in various concentrations (from 4.0/~g/ml to 1.0 mg/ml) to gastric fluid produced color changes that ranged from light orange to dark red. The clinical history and test results from 11 patients are summarized in Table I. Patient ages ranged from 11 to 32
0022-3476/79/600940+ 0350030/0 9 1979 The C. V. Mosby Co.