Hematopoietic dysplasia and marrow hypocellularity in children: A preleukemic condition

June 1982 The Journal o f P E D I A T R I C S

907

Hematopoietic dysplasia and marrow hypocellularity in children." A preleukemic condition Seven children with hematopoietic dysplasia were identified by morphologic criteria. The peripheral blood and bone marrow findings in these children were characterized by macro-ovalocytosis, progressive marrow hypoplasia, proteinaceous debris in the marrow interstices, and megaloblastoid changes. Six o f the patients had major constitutional abnormalities including coarse or unusual Jacies (4), short stature (4), and mental retardation (4). These children were prone to recurrent bacterial infections prior to the onset o f documented leukopenia. Chromosome studies of blood and bone marrow demonstrated a clonal abnormality involving the B, C, and E groups in 3/5 patients. An increase in the number of spontaneous chromosome breaks or radial figures was not observed. CFU-Cs were uniformly decreased in 5/5 patients, prior to the onset of leukopenia in one. Incomplete and transient responses to folic acid (3/4), androgens (1/4), and steroids (3/3) were noted. There were no responses to vitamin B12 in three patients or to ATG or other immunosuppressive therapies in four patients. One child has a sustained response to pyridoxine and one has had successful hematopoietie reconstitution by bone marrow transplantation. Three of the patients developed myelogenous leukemia 13, 47, and 100 months, respectively after presentation. Two have died from leukemia and one from intracranial hemorrhage. Children with HD differ morphologically and clinically from adults with "the preleukemic syndrome" by manifesting marrow hypocellularity and constitutional abnormalities. Both groups are at high risk for the development of progressive pancytopenia and myelogenous leukemia. Unlike those with Fanconi anemia, these children respond poorly to treatment with androgens and steroids. Results of bone marrow transplantation in one of the patients are encouraging.

Nathan L. Kobrinsky, M.D., Mark E. Nesbit, Jr., M.D., Norma K. C. Ramsay, M.D., Diane C. Arthur, M.D., William Krivit, M.D., Ph.D., and Richard D. Brunning, M.D.,* Minneapolis, Minn.

HEMATOPOIETIC DYSPLASIA in adults has been increasingly recognized as an evolutionary phase in the development of some cases of acute myelogenous leukemia, l In From the Department of Pediatrics and Department of Laboratory Medicine and Pathology, University of Minnesota. Supported in part by Hematology Research Training Grant: 2T32-HLO7145-O6A1, Childrens Cancer Study Group CA-07306, and Clinical Cancer Education Grant CA-19527. *Reprint address: Box 198, Mayo Memorial Bldg., 420 Delaware St., S.E., University of Minnesota, Minnepolis, MN 55455.

0022-3476/82/060907+07500.70/0 9 1982 The C. V. Mosby Co.

childhood, H D has been described retrospectively after the development of acute myelogenous leukemia. 2-6 However, the natural history and potential etiologic factors have not been clearly defined. Abbreviations used ATG: anti-thymocyte globulin CFU-C: colony-forming unit-soft agar culture assay H D: hematopoietic dysplasia HGB: hemoglobin PLT: platelet RBC: red blood cell WBC: white blood cell

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The Journal of Pediatrics June 1982

Table I. Hematopoietic dysplasia: Clinical features Patient

Age (yr) at onset

Sex

Clinieal findings

Physical findings

1

1 5/12

M

2

15 1/ 12

M

Microcephaly, unusual facies with protruberant ears; hyperpigmentation, eczema; umbilical and inguinal hernias, penoscrotal hypospadias, micropenis; metatarsus adductus Coarse facies, height < 3 percentile; widespread verrucae

3

5 2/12

M

4

1 8/12

F

5 6

15 10/12 1 1/12

M M

7

8/12

M

Mental retardation, seizures, apraxia, hyperactive behavior disorder; von Willebrand disease, mild Factor IX deficiency; recurrent otitis media, urinary tract infections Mild mental retardation, seizures; sociopathic personality; recurrent epistaxis; recurrent perirectal abcesses, staphylococcal pneumonia Mild mental retardation, recurrent epistaxis; recurrent otitis media; hepatitis A, B, non-A/ non-B; pseudomonas sepsis, E. coli sepsis 2 times Developmental delay, apraxia, failure to thrive; pancreatic insufficiency; recurrent otitis media, staphylococcal pneumonia; facial cellulitis Ache, otherwise normal Aminoaciduria (alanine, ~-aminobutyric acid, asparagine); recurrent otitis media and bronchitis; hypothyroidism; bleeding gums; photophobia; failure to thrive Neonatal feeding difficulties; juvenile-onset diabetes mellitus; recurrent streptococcal pharyngitis

in the present study, the clinical, laboratory, morphologic, chromosome, and C F U - C findings in seven cases of HD, identified by morphologic criteria, are presented. Although constitutional abnormalities (6/7 cases) and progressive pancytopenia (6/7 cases) are features, the marrow morphology and lack of chromosome fragility, demonstrated by the mitomycin C stress test and by an absence of spontaneous chromosome breaks and radial figures, confirm that these are not "Fanconi variants." MATERIALS

AND METHODS

A computer search was performed for all patients less than 18 years of age who were evaluated from January,

F a m i l y history

Juvenile-onset diabetes mellitus (maternal uncle)

"Childhood leukemia" (sister), refractory anemia (brother and sister), "elliptocytosis" (twin nephews)

Coarse facies with protruberant ears; Height < 3 percentile; weight < 3 percentile; hyperpigmentation

Childhood erythroleukemia (maternal uncle)

Unusual facies; height < 3 percentile; weight < 3 percentile; hepatomegaly; eczema

Negative

Hydrocoele Eczema; sparse hair; dysplastic teeth; hyperpigmentation; height < 3 percentile; weight < 3 percentile

Negative Negative

Malrotated kidney, genu valgus

"Anemia" (mother, maternal aunt)

1970, to January, 1981, at the University of Minnesota Hospitals for any type of cytopenia. Bone marrow smear and biopsy reports from 760 patients were reviewed. Seven patients (Patients 1 to 7) were identified who had cytologic and histologic features similar to those found in "preleukemia" in adults. The original peripheral blood and bone marrow smears and bone marrow biopsies from these patients were examined by one of the authors (R. D. B.). Hospital and outpatient records of these patients were reviewed. Peripheral blood and bone marrow smears were stained by routine hematologic techniques. Bone marrow trephine biopsies were obtained from the posterior iliac spines and

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Hematopoietic dysplasia and marrow hypocellularity

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Figure. Bone marrow section showing hypocellularity and proteinaceous debris. (Hematoxylin and eosin; • processed according to previously described methods. 7 Banded karyotype analysis of bone m a r r o w was performed by the method of Hozier and Lindquist. 8 T h e mitomycin C stress test for the diagnosis of Fanconi a n e m i a was performed according to the technique of Cervenka et al. 9 The method of Pike and Robinson ~~was used for the soft agar bone marrow culture assay for semi-differentiated myeloid stem cells. CASE REPORT In August, 1977, a 4 9/12-year-old white boy was noted to be anemic on preschool screening. He had been previously well except for episodes of recurrent otitis media and streptococcal pharyngitis. He was thought to be of "dull normal" intelligence. No response was noted to a three-month course of oral iron therapy. In January, 1978, he was re-evaluated for pallor, fever, bruising, and epistaxis, and he had a white blood cell count of 2,500/mm 3. His bone marrow trephine biopsy section was moderately hypocellular; the bone marrow smear exhibited striking hematodysplasia. A 47,XY,+8 clone was identified in the bone marrow cells at this time. Significant physical findings included a rather coarse facies, thin hair, protuberant ears, mild hepatomegaly, and short (< fifth percentile) stature. The child's maternal uncle had died of erythroleukemia at 7 years of age. A younger brother was under care for deafness secondary to recurrent otitis

media and mastoiditis. The patient was treated expectantly with antibiotics and blood product support. From August, 1979, to November, 1980, he was treated sequentially with three courses of antithymocyte globulin, high doses of methylprednisolone, 6-mercaptopurine, and androgens. In November, 1980, a bone marrow examination revealed marked hypocellularity, monoblasts, and hematodysplasia of the remaining myeloid cells; the 47,XY,+8 clone was again identified in both marrow and peripheral blood cells. Following cytoreduction with cyclophosphamide and total body irradiation, the child received an altogeneic bone marrow transplant from his HLA-haploidentical, MLC identical mother. He is presently five months post bone marrow transplantation and has developed mild graft-versus-host disease. He has no evidence of leukemia, is free of blood product support, and demonstrates a normoeellular, morphologically intact marrow.

RESULTS

Clinical features (Table I). All patients had constitutional abnormalities except for Patient 5, whose only associated clinical problem was a hydrocoele. Although a characteristic clinical syndrome was not identified, there were several commonly noted features, including: coarse or unusual facies (4), short stature (4), mental r e t a r d a t i o n (4), and skin abnormalities, particularly eczema (3), and

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The Journal o f Pediatrics June 1982

Table II. CFU-Cs in hematopoietic dysplasia in childhood

Patient

2 3 Pre-ATG Post-ATG 4 5 Pre-ATG Post-ATG 6 Pre-pyridoxine Post-pyridoxine Normal range

Cell line involved when studied

Colonies* > 50 cells day 14

All All All All All All RBC RBC

0 10 0 6 11 0 0 29 30-150

RBC = Red bloodcell;ATG = antithymocyteglobulin. *Counts per 200,000 nucleatedbone marrowcellsplated.

hyperpigmentation (3). Other abnormalities involved the central nervous system: behavior disorders (2), seizures (2), apraxia (2), and microcephaly (1); the genitourinary system: inguinal hernias or hydrocoele (2), malrotated kidney (1), micropenis and hypospadias (1); the skeletal system: metatarsus adductus (1) and genu valgus (1); the coagulation system: Factor IX deficiency (1) and von Willebrand disease (1); and the endocrine system: failure to thrive (2), juvenile-onset diabetes mellitus (1), and hypothyroidism (1). Exocrine pancreatic insufficiency was confirmed in one patient. However, subclinical fat malabsorption, perhaps related to pancreatic insufficiency, was identified by an elevated fecal fat content and low levels of fat soluble vitamins A and E in 3/4 additional patients. Recurrent bacterial infections including otitis media (5), pneumonia (2), urinary tract infections (1), cellulitis (1), and perirectal abscess (1) antedating the onset of documented leukopenia were noted in the six patients with constitutional abnormalities. Several viral (disseminated varicella in Patient 1) and fungal (Candida pneumonia in Patient 1 and Aspergillus pneumonia in Patient 4) illnesses were also noted, but developed as terminal events following leukemic evolution. Quantitative values for IgA, IgG, IgM, and IgE were normal in all patients. Studies of cell-mediated immunity were not consistently performed. Although abnormalities in mitogen (3/5) and skin test (1/2) responsiveness were identified, their significance is unclear.

Hematology and laboratory. Peripheral blood smears. The peripheral blood smears

from all patients manifested increased anisopoikilocytosis and macrocytes. Basophilic stippling and oval macrocytes were noted in some of the patients. Nuclear hypose[gmentation (pseudo-Pelger-Huet changes) was noted in varying numbers of neutrophils in all patients. Neutrophils with

apparently diminished specific granule formation were found in four patients. A slight increase in basophils was found in two patients. Bone m a r r o w smears. The bone marrow smears were characterized by abnormalities in the three major cell lines: erythroblasts, granulocytes, and megakaryocytes. Although there was some variability in the manifestations in the different patients, developing erythroid cells appeared to show the most striking abnormalities. This was characterized by nuclear lobulation and karyorrhexis, multinucleation, and megaloblastoid changes. "Ringed" sideroblasts were found in two patients. Cytoplasmic vacuolization was a prominent feature of the precursor cells in one patient. Developing neutrophils with retarded nuclear segmentation and apparently diminished specific granules were present. Less commonly, neutrophils with bizarre, lobulated nuclei were found. Megakaryocytes were usually decreased but were increased in one patient. Micromegakaryocytes were noted in smears from most patients. Bone m a r r o w biopsies. Bone marrow trephine biopsy sections were hypocellular in five patients and hypercellular in two. In the biopsy sections from four patients there were scattered areas of apparent marrow damage characterized by the deposition of a lightly eosinophilic amorphous debris in the interstices (Figure). Myelofibrosis was not identified in any of the marrow sections. Laboratory studies. Several characteristics of "stressed" myetopoiesis and erythropoiesis described in adults with the preleukemic syndrome ~were identified. These included elevated leukocyte alkaline phosphatase values (3/4), elevated serum vitamin B~2 levels (5/6), elevated i antigen (5/5) and hemoglobin F (5/5), and increased mean corpuscular volume (5/5). Red cell folate levels were normal in all cases evaluated (5/5). Serum folate concentrations were low in Patients 2 (1.2 ng/ml) and 4 (2.4 ng/ml), both "of whom had laboratory evidence of fat malabsorption. Soft agar culture (CFU-C) studies (Table II). Pretherapy colonies, greater than 50 cells, enumerated on day 14 were significantly decreased compared to normal values. In Patient 6 these decreases were noted prior to the development of leukopenia. Cytogenetie studies (Table III). None of the patients evaluated had an increased number of spontaneous chromosome breaks or radial figures. The mitomycin C stress test was negative in the two patients studied. Clonal abnormalities were identified in unstimulated Giemsabanded bone marrow preparations in 3/5 patients studied. These abnormalities were different in each case and involved chromosomes of the B, C, and E groups. After leukemic evolution, the 47,XY,+8 abnormality in Patient

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Hematopoietic dysplasia and marrow hypocellularity

911

Table IlL Cytogenetic studies in hematopoietic dysplasia in childhood Blood Patient

No. cells studied

2 3 4

. 30 20 23

5 6

-30

7

.

1

No. abnormal

Bone marrow No. cells. studied

Karyotype

. 0 2 0

. . 46,XY 46,XY/47,XY,+8 46,XX

-0

46,XY

.

--

.

.

No. abnormal

.

Mitomycin C stress test

Karyotype

. 14 12 12

4 12 12

10 35

0 0

46,XY/46,XY,deI(I 7)(q22) 47,XY,+8 47,XX,-4,+der(mar),t( 1;4) ( I qter----1q 11 ::4q35---~4qter),+ det(6)(q22) 46,XY 46,XY

.

.

Negative -Negative --

--

.

Table IV. Hematologic evolution: Time from initial evaluation to manifestation (mo) Patient

Anemia

Thrombocytopenia

Neutropenia

Leukemia

] Outcome

Comments

r

100

103 ~"

1

100

88

0

2

19

17

0

0*

403

3

0

0

0

47*

513

4 5 6

0 0 0

0 0 0

1 0 9

13" ---

157 4~ 403

7

0

--

28

1013

Terminal disseminated varicella; Candida and Pasteurella multocida pneumonia; Pseudomonas urinary tract infection "Terminally ill" by report; withdrawal from medical care by family; lost to follow-up Bone marrow transplant; mild graft versus host disease; normal hematopoietic function; no evidence of recurrent leukemia Aspergillus pneumonia Cerebral hemorrhage Response to pyridoxine; mild thrombocytopenia and neutropenia persist Transfusion dependent

0 = Present at initial evaluation. *Clonal abnormality. fDied. :[:Aliveat last evaluation (March 1981)

3 was present in both bone marrow and peripheral blood but not in normal somatic tissue (cultured skin fibroblasts), thus excluding a congenital trisomic condition. EVOLUTION Patients presented with cytopenias involving one (3), two (2), or three (2) cell lines at diagnosis. Pancytopenia eventually developed in six patients. Three patients developed acute myelogenous leukemia at 13, 47, and 100 months after onset (Table IV). Multiple therapeutic approaches were utilized. A partial response to folate was noted in 3 / 4 patients, two of whom had low serum but normal R B C levels and biochemical evidence of malabsorption. This response was not associated with morphologic improvement and was not sustained. Partial but unsustained responses were also noted

to androgen (1/4) and to steroid therapy (3/3). A sustained response to treatment with pyridoxine was noted in 1/4 patients (Patient 6), a boy with "ringed" sideroblasts. Patient 3 has had sustained hematopoietic reconstitution with no evidence of recurrent leukemia seven months following bone marrow transplantation. N o response was noted to A T G or other immunosuppressive therapies (0/4), or to vitamin B~2 (0/3). At a median follow-up of 3 8/12 years (range, 4/12 to 8 7/12 years), three children have died, one is "terminally ill," one is transfusion dependent, and two are clinically well and transfusion independent. DISCUSSION Hematopoietic dysplasia ("the preleukemic syndrome") has been increasingly recognized in adults since the review

9 12

Kobrinsky et al.

of the clinical features and hematologic evolution by Saarni and Linman in 1973 H and Linman and Bagby? 2 Typically, patients present with unexplained cytopenias which over the course of months to years develop into pancytopenia or overt myelogenous leukemia. This progression suggests the possibility of underlying stem cell damage and attrition with decreased and abnormal CFU-Cs and the evolution of a chromosomally defined malignant clone. 13 This possible stem cell damage may result from a variety of insults, including toxins, chemotherapy, radiation, and possibly "aging. ''~4'~5 The cases of HD in the present report are morphologically quite similar to those previously described in adults. Two differences, however, are noted: HD in adults is generally associated with marrow hypercellularity as well as a tendency to increased numbers of megakaryocytes. Marrow hypocellularity (5/7) and decreased numbers of megakaryocytes (6/7), on the other hand, were more common in our patients. The six cases of preleukemia in children described by Blank and Lange 2 closely resemble our patients and were also associated with decreased numbers of megakaryocytes; however, the marrow cellularity prior to the onset of leukemia was not described. Although the erythroid changes in some patients resembled those seen in congenital dyserythropoietic anemia, ~6 the absence of prominent nuclear bridging and the involvement o f other cell lines are distinguishing features. The hematologic evolution described in adults and in this study are similar: six of the seven patients developed pancytopenia, and three developed myelogenous leukemia at a median of 57.5 months after observation of the marrow abnormalities, The most striking clinical feature of our patients is the ]gresence of major constitutional abnormalities, particularly affecting the central nervous and integumentary systems and somatic growth. This finding is not a feature of adult HD. Bone marrow damage in the study patients may have been caused by unknown metabolic disorders or by insults occurring during embryogenesis. The family history of "refractory anemia, childhood leukemia, and hereditary elliptocytosis" in Patient 2 and of well-documented childhood erythroleukemia in Patient 3 suggests the role of hereditary factors. In Patient 6, the finding of aminoaciduria (alanine, a-aminobutyric acid, and asparagine) and response to pyridoxine suggest a metabolic defect. An abnormality in embryogenesis is suggested by the association of HD with the Schwachman syndrome, a constitutional hypoplastic anemia and pancreatic insufficiency. Woods et a117,18and Huijgens et a119have described three cases of Schwachman syndrome and HD which progressed to myelogenous leukemia. The occurrence of

The Journal of Pediatrics June 1982

pancreatic insufficiency or fat malabsorption in many of our patients is to be noted. However, we do not believe that these are examples of the Schwachman syndrome, except for Patient 4. Furthermore, Pearson et aF ~ have described four additional children with refractory sideroblastie anemia with vacuolization of marrow precursors and exocrine pancreatic dysfunction. Though our patients were similar in many ways, vacuolization was not a feature of the present series. Pancreatic insufficiency was diagnosed by intestinal aspirate enzyme analysis and postmortem examination in Patient 4 (Patient 1 of Woods et aW), and increased fecal fat and decreased levels of the fat-soluble vitamins A and E suggested subclinical pancreatic insufficiency in two patients. Confirmatory studies, however, were not performed. Other constitutional disorders such as Kostmann agranuloeytosis, Down syndrome, Bloom syndrome, and Diamond-Blackfan syndrome, although associated with an increased incidence of acute myelogenous and acute lymphocytic leukemia, have not been associated with HD and have historically been considered separately from "preleukemia.,,1.3 Fanconi anemia and idiopathic aplastic anemia, though associated with macroeytosis, elevated i antigen and hemoglobin F, features of stress erythropoiesis, do not demonstrate other features of HD; erythroid and myeloid elements are severely depleted but cytologically normal. Hematopoietic dysplasia may be more common in children than has previously been recognized. The diagnosis should particularly be considered in patients with constitutional abnormalities, cytopenias, and dysmorphic features on the peripheral blood smear including macroeytosis, normoblastemia, disordered nuclear segmentation of the neutrophils, and hypogranular-agranular neutrophils and platelets. Dysmorphic features of bone marrow smears are diagnostic and uniformly associated with decreased CFU-Cs. The response to pyridoxine in one of our patients and the lack of response to ATG in others were reflected in vitro by concomitant changes to CFU-Cs. The CFU-C assay may be a sensitive indicator of developing HD and a predictor of clinical responsiveness to various therapeutic modalities. Treatment results have been generally unsatisfactory in patients with HD. A transient peripheral response to folate was noted in three of our patients,-two of whom had low serum but normal RBC values and evidence of fat malabsorption. The third responder was not evaluated for fat malabsorption but failed to thrive clinically. Pyridoxine completely reversed the hematologic disorder in one child. Both of these hematinic agents should be tried after appropriate studies in all cases. Once established, HD may progress to complete panty-

Volume 100 Number 6

topenia, poorly responsive to steroid a n d androgen therapy, and myelogenous leukemia. Bone marrow t r a n s p l a n t a t i o n resulted in complete hematopoietic reconstitution of one of the present patients. This therapy m a y be efficacious in the t r e a t m e n t of this problem.

REFERENCES 1. Linman JW, and Bagby GC Jr: The preleukemic syndrome (hematopoietic dysplasia), Cancer 42:854, 1978. 2. Blank J, and Lange B: Preleukemia in children, J PEDIATR 98:565, 1981. 3. Kleihauer E: The preleukemic syndromes (hematopoietic dysplasia) in childhood, Eur J Pediatr 133:5, 1980. 4. Krishnan EV, Wegner K, and Garg SK: Congenital hypoplastic anemia terminating in acute promyeloeytic leukemia, Pediatrics 61:898, 1978. 5. Rosenberg HS, and Taylor FM: The myeloproliferative syndrome in children, J PEDIATR 52:407, 1958. 6. Teasdale JM, Worth A J, and Corey M J: A missing C group chromosome in the bone marrow cells of three children with myeloproliferative disease, Cancer 25:1468, 1970. 7. Brynes RK, McKenna RW, and Sundberg RD: Bone marrow aspiration and trephine biopsy, Am J Clin Pathol 70:753, 1978. 8. Hozier JC, and Lindquist LL: Banded karyotypes from bone marrow: a clinical useful approach, Hum Genet 53:205, 1980. 9. Cervenka J, Arthur D, and Yasis C: Mitomycin C test for diagnostic differentiation of idiopathic aplastic anemia and Fanconi anemia, Pediatrics 67:119, 1981. 10. Pike BE, and Robinson WA: Human bone marrow colony growth in agar gel, J Cell Physiol 76:77, 1970.

Hematopoietic dysplasia and marrow hypocellularity

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11. Saarni ML, and Linman JW: Preleukemia: The hematologic syndromes preceeding acute leukemia, Am J Med 55:38, 1973. 12. Linman JW, and Bagby GC Jr: The preleukemic syndrome: Clinical and laboratory features, natural course and management, Blood Cells 2:11, 1976. 13. Pierre RV: Cytogenetic studies in preleukemia: Studies before and after transition to acute leukemia in 17 subjects, Blood Cells 1:163, 1975. 14. Kobrinsky NL, Robison LL, and Nesbit ME Jr: Acute non-lymphocytic leukemia, Pediatr Clin North Am 27:345, 1980. 15. Fouear K, McKenna RW, Bloomfield CD, Bowers TK, and Brunning RD: Therapy-related leukemia, a panmyelosis, Cancer 43:1285, 1979. 16. Punt K, Borst-Eilers E, and Nijessen JG: Congenital dyserythropoietic anemia, Type I! (HEMPAS), in Lewis SM, and Verwilghen RE, editors: Dyserythropoiesis, New York, 1977, Academic Press, Inc., p 71. 17. Woods WG, Krivit W, Lubin BH, and Ramsay NKCR: Clinical variability of the Schwachman Syndrome: In vivo and in vitro observations, Am J Pediatr Hematol Oncol (in press). 18. Woods WG, Roloff JS, Lukens JN, and Krivit W: The occurrence of leukemia in patients with the Schwachman syndrome, J Pediatr 99:425, 1981. 19. Huijgens PC, Van der Vern EA, Meijer S, Muntinghe OG: Syndrome of Schwachman and leukemia, Scand J Hematol 18:20, 1977. 20. Pearson HA, Lobel JS, Kocoshis SA, Naiman JL, Windmiller J, Lammi AT, Hoffman R, and Marsh JC: A new syndrome of refractory sideroblastic anemia with vacuolization of marrow precursors and exocrine pancreatic dysfunction, J PEDIATR 95"976, 1979.