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EFFECT OF FOOD ON ZINC ABSORPTION
217 EFFECT OF FOOD ON ZINC ABSORPTION
SIR,-As we pointed out earlier (July 21, p. 154) the absorption of zinc is slight during the early period of oral intake and a significant increase in serum levels can be demonstrated only after about six weeks. After reading the letter by Dr. Schelling and others (Oct. 27, p. 968) about the effect of food on zinc absorption, we could, only agree that absorption of zinc is somewhat impaired by food. In one group of healthy volunteers who consumed 600 mg ZnS04’7H20 per day for three months, we found the maximum serum levels after about six weeks. Knowing the nauseating effect of zinc sulphate on fasting subjects, we instructed the volunteers to consume the metallic compound with proper meals and blood samples were taken always in the morning. In 2 subjects we found, however, rather high amounts of zinc in the serum (300 and 350 ug. per 100 ml. compared with 150 j.Lg. per 100 ml. in the others). In these two subjects who were not used to eating breakfast, we found increases in the serum concentrations of zinc from the second week of oral intake. This seems to agree with the results of Dr Schelling and others in fasting subjects who consumed zinc sulphate. If the absorption of zinc is impaired by food oral zinc therapy in patients with gastroenterological and other disorders may not be fully effective. The amounts of serum-zinc levels found in a selected group of patients from the medical clinic of Lund Hospital and the response to oral zinc therapy are shown in the accompanying table. SERUM-ZINC LEVELS IN A GROUP OF PATIENTS
Oral zinc therapy helped in some cases to brin;g the serum-zinc levels to normal or slightly higher values, but in other cases, the increase was only slight. It seems that the absorption of zinc varies in disease and does not show a definite uniform pattern after oral zinc therapy. We have not yet studied the effect of food on zinc absorption and it is clear from the findings of Dr Schelling and his colleagues that this factor has to be taken into consideration in oral zinc therauv. University Hospital, S-221 85 Lund, Sweden.
M. ABDULLA A. NORDÉN
PLASMA-ZINC IN SICKLE CELL-ANAEMIA
SiR,-Two articles1,2 which reported the efficacy of oral zinc sulphate for the healing of chronic leg ulcers extensive correspondence"-9 including replies prompted by the authors of the articles.I,9 The experience of these investigators is varied, with oral zinc therapy either adding nothing to the healing of the leg ulcers5," or greatly accelerating the healing of such ukers.1.2 In a study of 34 patients with sickle-cell anaemia, Serjeant et a1.’o reported that the healing rate of leg ulcers m the patients treated with oral zinc sulphate was three times faster than in the placebo group. Serum-zinc levels BBere found to he lower in the patients with sickle-cell anaemia than in normal subjects or individuals with sickle-cell trait. There was no correlation between serumzinc level and response to oral zinc sulphate therapy in terms of leg ulcer healing. Talbot and Ross" had found an
Plasma-zinc levels in sickle-cell anaemia (SS), in sickle-cell trait (AS), and in normal individuals (AA). PLASMA-ZINC LEVELS IN PATIENTS WITH SICKLE-CELL DISEASE AND SICKLE-CELL TRAIT
slightly increased levels of erythrocyte zinc in 3 of 5 patients with sickle-cell anaemia. We have measured plasma-zinc levels by atomic absorption spectrophotometry in 50 patients with sickle-cell anaemia, 50 individuals with sickle-cell trait, and 50 normal individuals, all confirmed by haemoglobulin electrophoresis. Our results (see table and accompanying figure) indicate that plasma-zinc levels in patients with sickle-cell disease are significantly decreased compared to normal controls. Our results thus confirm those reported in the nrevious studv. GUNGOR KARAYALCIN Queens Hospital Center Affiliation FRED ROSNER of the Long Island JewishKIR Y. KIM Hillside Medical Center, PRADEEP CHANDRA N.Y. U.S.A. Jamaica, 11432, Husain, S. L. Lancet, 1969, i, 1069. Greaves, M. W., Skillen, A. W. ibid. 1970, ii, 889. Auckland, G. ibid. p. 1032. Shapiro, S, Siskind, V. ibid. p. 1132. 5. Myers, M. B. ibid. p. 1253. 6. Clayton, R. J. ibid. p. 1254. 7. Husain, S. L., Fell, G. S., Scott, R. ibid. 1970, ii, 1261 8. Trethewie, E. R. ibid. 1970, ii, 1362. 9. Greaves, M. W., Skillen, A. W. ibid. 1971, i, 96. 10. Serjeant, G. R., Galloway, R. E., Gueri, M. C. ibid. 1970, ii, 1. 2. 3. 4.
891. 11. Talbot, T. R. Jr. Ross. J. F. Lab Invest. 1960. 9, 174.
SMALL DOSES OF INTRAMUSCULAR INSULIN IN DIABETIC "COMA" IN CHILDREN
SIR,-After a discussion with Professor Alberti, a simple scheme adapting his technique of hourly intramuscular injection of small doses of insulin (Sept. 8, p. 515) to the management of diabetic coma in children has been devised. So far, it has been used in four patients with com-
despite the severity of the acidosis; in three pH was below 7.1. The advantages are the simplicity of management with a smooth and preciictahle relief of coma, hyperventilation, and hyperglycaemia over a period which averages seven hours, without any fear of hypoglvcaemia. The laboratory is only needed to provide biochemical assessment on ad-
plete
success,
of them the blood
mission and after
an
interval of two hours after the
SIR,-As we pointed out earlier (July 21, p. 154) the absorption of zinc is slight during the early period of oral intake and a significant increase in serum levels can be demonstrated only after about six weeks. After reading the letter by Dr. Schelling and others (Oct. 27, p. 968) about the effect of food on zinc absorption, we could, only agree that absorption of zinc is somewhat impaired by food. In one group of healthy volunteers who consumed 600 mg ZnS04’7H20 per day for three months, we found the maximum serum levels after about six weeks. Knowing the nauseating effect of zinc sulphate on fasting subjects, we instructed the volunteers to consume the metallic compound with proper meals and blood samples were taken always in the morning. In 2 subjects we found, however, rather high amounts of zinc in the serum (300 and 350 ug. per 100 ml. compared with 150 j.Lg. per 100 ml. in the others). In these two subjects who were not used to eating breakfast, we found increases in the serum concentrations of zinc from the second week of oral intake. This seems to agree with the results of Dr Schelling and others in fasting subjects who consumed zinc sulphate. If the absorption of zinc is impaired by food oral zinc therapy in patients with gastroenterological and other disorders may not be fully effective. The amounts of serum-zinc levels found in a selected group of patients from the medical clinic of Lund Hospital and the response to oral zinc therapy are shown in the accompanying table. SERUM-ZINC LEVELS IN A GROUP OF PATIENTS
Oral zinc therapy helped in some cases to brin;g the serum-zinc levels to normal or slightly higher values, but in other cases, the increase was only slight. It seems that the absorption of zinc varies in disease and does not show a definite uniform pattern after oral zinc therapy. We have not yet studied the effect of food on zinc absorption and it is clear from the findings of Dr Schelling and his colleagues that this factor has to be taken into consideration in oral zinc therauv. University Hospital, S-221 85 Lund, Sweden.
M. ABDULLA A. NORDÉN
PLASMA-ZINC IN SICKLE CELL-ANAEMIA
SiR,-Two articles1,2 which reported the efficacy of oral zinc sulphate for the healing of chronic leg ulcers extensive correspondence"-9 including replies prompted by the authors of the articles.I,9 The experience of these investigators is varied, with oral zinc therapy either adding nothing to the healing of the leg ulcers5," or greatly accelerating the healing of such ukers.1.2 In a study of 34 patients with sickle-cell anaemia, Serjeant et a1.’o reported that the healing rate of leg ulcers m the patients treated with oral zinc sulphate was three times faster than in the placebo group. Serum-zinc levels BBere found to he lower in the patients with sickle-cell anaemia than in normal subjects or individuals with sickle-cell trait. There was no correlation between serumzinc level and response to oral zinc sulphate therapy in terms of leg ulcer healing. Talbot and Ross" had found an
Plasma-zinc levels in sickle-cell anaemia (SS), in sickle-cell trait (AS), and in normal individuals (AA). PLASMA-ZINC LEVELS IN PATIENTS WITH SICKLE-CELL DISEASE AND SICKLE-CELL TRAIT
slightly increased levels of erythrocyte zinc in 3 of 5 patients with sickle-cell anaemia. We have measured plasma-zinc levels by atomic absorption spectrophotometry in 50 patients with sickle-cell anaemia, 50 individuals with sickle-cell trait, and 50 normal individuals, all confirmed by haemoglobulin electrophoresis. Our results (see table and accompanying figure) indicate that plasma-zinc levels in patients with sickle-cell disease are significantly decreased compared to normal controls. Our results thus confirm those reported in the nrevious studv. GUNGOR KARAYALCIN Queens Hospital Center Affiliation FRED ROSNER of the Long Island JewishKIR Y. KIM Hillside Medical Center, PRADEEP CHANDRA N.Y. U.S.A. Jamaica, 11432, Husain, S. L. Lancet, 1969, i, 1069. Greaves, M. W., Skillen, A. W. ibid. 1970, ii, 889. Auckland, G. ibid. p. 1032. Shapiro, S, Siskind, V. ibid. p. 1132. 5. Myers, M. B. ibid. p. 1253. 6. Clayton, R. J. ibid. p. 1254. 7. Husain, S. L., Fell, G. S., Scott, R. ibid. 1970, ii, 1261 8. Trethewie, E. R. ibid. 1970, ii, 1362. 9. Greaves, M. W., Skillen, A. W. ibid. 1971, i, 96. 10. Serjeant, G. R., Galloway, R. E., Gueri, M. C. ibid. 1970, ii, 1. 2. 3. 4.
891. 11. Talbot, T. R. Jr. Ross. J. F. Lab Invest. 1960. 9, 174.
SMALL DOSES OF INTRAMUSCULAR INSULIN IN DIABETIC "COMA" IN CHILDREN
SIR,-After a discussion with Professor Alberti, a simple scheme adapting his technique of hourly intramuscular injection of small doses of insulin (Sept. 8, p. 515) to the management of diabetic coma in children has been devised. So far, it has been used in four patients with com-
despite the severity of the acidosis; in three pH was below 7.1. The advantages are the simplicity of management with a smooth and preciictahle relief of coma, hyperventilation, and hyperglycaemia over a period which averages seven hours, without any fear of hypoglvcaemia. The laboratory is only needed to provide biochemical assessment on ad-
plete
success,
of them the blood
mission and after
an
interval of two hours after the