Cellular immune deficiency with autoimmune hemolytic anemia in purine nucleoside phosphorylase deficiency

Cellular Immune Deficiency with Autoimmune Hemolytic Anemia in Purine Nucleoside Phosphorylase Deficiency

KENNETH WILLIAM

C. RICH, M.D. J. ARNOLD,

M.D.

Chicugo Illinois THOMAS PALELLA, M.D. IRVING H. FOX, M.D. Ann Arbor, Michigan

Immunologic and metabolic abnormalities were studied in a five year old boy with 0.07 per cent of normal erythrocyte purine nucleoside phosphorylase activity. The clinical course is characterized by severe autoimmune hemolytic anemia, a transient neurologic disorder with tremor and ataxia, and minor infectious illnesses. There is severe lymphopenia with decreased absolute numbers of T and B lymphocytes. Mitogen-stimulated blastogenesis is reduced, but response to allogeneic lymphocytes is normal. A monoclonal IgG protein is present. There is hypouricemia, elevated plasma inosine level, hypouricosuria and an increase in the urinary concentration of inosine and guanosine. The pattern of heterozygote distribution in the patient’s family is compatible with an autosomal recessive trait in which heierozygotes are identifiable. In addition, the unusual laboratory and clinical manifestations of this patient illustrate the heterogeneity of the clinical syndrome associated with purine nucleoside phosphorylase deficiency. Inborn errors of purine nucleoside degradation are associated with disordered immune function. The deficiency of adenosine deaminase is associated with an impairment of T- and B-lymphocyte function [1,2] whereas the absence of purine nucleoside phosphorylase is characterized by T-lymphocyte dysfunction [3-Ill. An impairment of immunoglobulin synthesis is linked to ecto-Y-nucleotidase dgficiency

WI. From the Children’s Memorial Hospital, Department of Pediatrics, Northwestern University: Department of Medicine, University of Illinois College of Medicine: and the Human Purine Research Center, Department of Internal Medicine and Biological Chemistry, University of Michigan Medical Center. This study was supported by U.S. Public Health Service Grant AM 19674 and 5 MO1 RR-42, and Illinois Chapter of the Arthritis Foundation. It was published in abstract form in Pediatric Research 12: 485A. 1978. Requests for reprints should be addressed to the Division of Immunology, Children’s Memorial Hospital, 2300 Children’s Plaza, Chicago, Illinois 60614. Manuscript accepted December 7. 1979.

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July 1979

The

Purine nucleoside phosphorylase deficiency has been observed in seven patients from four families [3-111. Three families have a complete enzyme deficiency [3,6,9,11], whereas one family has a partial enzyme deficiency with a milder immune disorder [4,5,10]. We have recently observed a child with severe partial deficiency and unique immunologic and clinical features. A description of the immune and metabolic disturbances in this child is the subject of this report.

CASE REPORT This five year old Caucasian boy presented at age three with a prolonged upper respiratory tract illness. He had no previous history of severe illness. He received the usual course of childhood immunizations without complication, and his growth and development were normal except for a delay in walking until 18 months of age. Family history is negative for immunodeficiency or collagen vascular disease. The parents are not related and are of Sicilian and Irish origin.

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PIIKINR NI I(:LEosIr)f+ PI~~SPH~RYLASE DEFIC:IENC:Y~~211 ET xL.

His first admission to Children’s Memorial Hospital at 35/J years of agt: \vas occasioned by a sudden decrease in hemoglobin. Physical examination revealed only rudimentary tonsils, no palpable lymph nodes, and a markedly enlarged liver and spleen. Neurologic examination did not disclose any abnormalities. Blood count showed 4,700 leukocytes/mm3 with 69 per cent ncutrophils, 9 per cent band forms, 6 per cent lymphocytes, $1per cent monocytcs, 6 per cent eosinophils and I per cent basophils. The hemoglobin level was 4.8 g/dl. Reticulocytc count was G.0 per cent. Bone marrow aspiration rcvealcd crythroid hypcrplasia and mild megaloblastic changes with cl normal number of plasma cells. The serum folatc was normal (23 mg/ml. normal > 2.3 mg/ml). Antinuclear antittc)tlics, thyroid antibodies ant1 antibodies against clo~~l~l~~-str;~ntIctlDNA were not present in the serum. The fourth component of complement ((24) and total hemolytic complement Icvcls were depressed (13 mg/dl and 19 per cent, rcspectivcly). hut the level of the third component of comI)lcmont ((X3) wx normal. Because of the persistence of the hcmolytic process, prednisonc therapy was started, 1.5 mg/ kg/tlay. Tho hc:mo#lohin lcvcl promptly rose and the C4 and total comolcmcnt levels returned to normal. The dose of prctlnisono was slowly tapered and discontinued after six months. The lymphocyte count was unaffected hy the steroids. At iig,: Q/q !.ears a rhythmic tremor of the left hand devclopc~l which was madc worse by activity. It progressed to in~rrlvc the I~oy’s left leg. and later the right leg and arm, and he I)c:c;lmc unahlt: to feed himself or to walk without assistance. Cognitive flmction. however, remained normal. Physical examination suggested a cerehellar outflow tract lesion, hut thorough evaluation four days and seven weeks after the onset of the tremor failed to show a structural or infectious etiology for the disorder. A brief trial of ACTH injections was given M.ithout bcncfit and thereafter the patient was treated with clc)nazep;+rn. Three months after the onset, the tremor began to regress and by five months after the onset. he had a mild residual left intention tremor and spasticity. ilrnl

MATERIAL

AND

METHODS

Imrnrlnoglol)lllins were determined hy radial immunodiffusion. ‘T’lymphocytes by sheep red cell rosettes (E rosettes). B lymphocytes by antibody and complement-coated sheep red cell roscttos (EAC rosettes) [13]. and monocytcs by histoc;hcmical stain for peroxidasc [14]. The proliferative response of lymphocytes was assayed by mitogcn stimulated microcultures (PIlA-P, Burroughs Welcome, Research Triangle, North (A~rolin;l) and by allogeneic cell-stimulated microcultllres [IS]. The crythrocytc purine enzyme levels were ass;q~:tl by prcviorlsly described methods [4]. Plasma and urinary inosinc and guanosine levels were measured by enzymatic sl,cctrot)h”tomctric assays which quantitated the conversion of inosine ;lntl guanosine to uric acid in the presence of purine nuclcosidc phosphorylasc and xanthine oxidasc. The nucleclsicl(, mcasllrcment incllltletl both 2oxy and 2’-deoxy dcriv;ltivos. RESULTS

Evaluation of Humoral Immune Function. B-lymphocyte function in this patient was intact as demon-

antI-NH5 NI anti-IgG Pt Figure 1. lmmunoelectrophoresis of serum from a patier with purine nucleoside phosphorylase deficiency. Note the distortion and thickening of the arc with IgG antiserum (arrow).

strated by the formation of specific antibody. Immunization with diphtheria as an infant resulted in the formation of neutralizing antibody and a nonreactive Schick test. Intercurrent influenza and parainfluenza infection resulted in a rise in the titers of complementfixing antibody ( 2. t 2.5 X lo5 mononuclear cells per culture. t 2.5 X lo5 mitomycin-C treated mononuclear cells per culture. l

TABLE Ill

Erythrocyte Enzyme Activity (nmol/hr/mg) Enzyme

Purine nucleoside phosphorylase Adenosine deaminase Hypoxanthine-guanine phosphori bosyltransferase Adenine phosphoribosyltransferase l

Figures in parentheses

Normal f SD

Patient

Father

Mother

2,166.4 f 575.9 (77)’ 58.8 f 13.8 (77)

1.5 43.5

986 34.7

907 33.6

128.4

101.9

101.2

41.9

18.6

19.4

103.9 f

15.9 (79)

24.5 f 5.8 (78)

indicate number of subjects assayed.

markers on three occasions showed only 18 to 27 per cent of the cells formed spontaneous sheep erythrocyte rosettes (T lymphocytes) compared to normal (normal, 53 to 85 per cent). Twenty-nine to 46 per cent of the cells, presumably B lymphocytes and monocytes, formed rosettes with antibody and complement-coated sheep erythrocytes (normal, 6 to 26 per cent). However, the proportion of peroxidase-containing monocytes in the mononuclear cell preparations was usually high [up to 40 per cent as compared to 14 f 4.2 per cent from normal donors). When corrected for monocyte contamination, the proportion of T-lymphocytes ranged from 25 to 45 per cent, and B-lymphocytes were 6 per cent. Thus, the absolute number of T and B lymphocytes and the proportion of T lymphocytes are significantly decreased. Evaluation of Purine Metabolism. The activity of purine nucleoside phosphorylase in the patient’s hemolysate using inosine as the substrate was 0.07 per cent

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July 1979

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of normal (Table III). Dialysis of the hemolysate for 2 hours at 4’C did not alter the activity. Mixing of patient hemolysate with normal hemolysate resulted in the expected 50 per cent of normal activity, suggesting that the low activity was not due to an inhibitor of the enzyme. Adenine phosphoribosyltransferase was substantially increased and erythrocyte PP-ribose-P concentration was 284 per cent above the normal control value at the time of assay of 0.76 PM. Hypouricemia and hypouricosuria were found [Table IV), and plasma and urinary inosine levels were elevated. Cerebrospinal fluid inosine concentration was similar to the plasma value. Guanosine was present in large quantities in the urine and detectable in spinal fluid. Oxypurine excretion in the urine was increased. The diminished serum mate concentrations and urine uric acid excretion with an elevated plasma inosine level and increased 24 hour guanosine and inosine ex-

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TABLE IV

NIICLEOSIIlE

PHOSPHORYLASE

Plasma Urate (mgidi) lnosine and deoxyinosine (PM) Urine Uric acid (mg/mg creatinine) Oxypurine (pmol/mg creatinine) inosine and deoxyinosine (~moi/mg creatinine) Guanosine and deoxyguanosine (pmoi/mg creatinine) Uric acid equivaientst/ creatinine (mg/mg) Cerebrospinal fluid lnosine and deoxyinosine (/.W Guanosine and deoxyguanosine (PM)

1.8 38.0

--RICH

ET .41..

-.

Purine Levels in Body Fluids in Purine Nucleoside Phosphorylase Deficiency Patient

DEFICIEN(:\r’

ATP+ R1bose5-P

11

NormalValue

PP-Rlbose-P+GIutomlne + 12 1

3.7 f 1.06‘ Undetectable

0.15 5.52

0.12 f 0.03+

15.7

0.05 f 0.04$

5.2

Undetectable

4.59