Hemophagocytosis.pdf

G RAND R OUNDS

Clinical Pathologic Conference: Ten-year-old with hepatosplenomegaly and bleeding from nose, gums, and mouth Mudra Kohli-Kumar, MD, Atilano G. Lacson, MD, Charlene Weber, MD, and Herbert H. Pomerance, MD

CASE PRESENTATION Charlene Weber, MD, and Herbert H. Pomerance, MD A 10-year-old boy with a febrile illness associated with frequent bleeding from the nose, gums, and mouth was examined in the emergency department. At 5 years of age, abdominal enlargement was noted. Imaging studies revealed massive hepatosplenomegaly of uncertain origin. This resolved spontaneously. Laboratory studies including bone marrow were not diagnostic. At age 8 years, he had a left Bell’s palsy that was treated with a 6-month course of prednisone. Four months later, his abdominal enlargement recurred. He had nonspecific abdominal pain and was again found to have severe hepatosplenomegaly. Antinuclear antibody level was 7 days, splenomegaly (≥3 cm below the costal margin), cytopenia, hypofibrinogenemia, and/or hypertriglyceridemia. Demonstration of hemophagocytosis supports the diagnosis but is by no means exclusive to these syndromes, as many other conditions (such as infection or hemolytic anemia) may be associated with the phenomenon of secondary hemophagocytosis. Not uncommonly, the bone marrow will not reveal hemophagocytosis, and examina610

tion of the spleen, lymph nodes, and liver may be more diagnostic. According to Henter et al,4 hemophagocytosis is not a necessary concomitant. History of consanguinity, death of siblings with similar presentation, past history with special emphasis on other symptoms suggestive of repeated infections, or immunodeficiency would be helpful in support of the diagnosis, but such history was not present. There was also no additional information regarding the duration, appearance, and course of the dermatologic lesions and pulmonary problems (including bronchoscopic findings). Chronic graft versus host syndrome, although it must be thought of, was not a serious consideration. I favor FHS or IAHS for the following reasons: multiorgan involvement; progressive, fatal course; episodic cytopenias, mild in nature; uninformative “routine” investigations including nondiagnostic bone marrow examinations; and increased triglyceride levels. Examination of other tissues such as liver, spleen, or lymph nodes may aid in the diagnosis. Dr Kumar’s diagnosis: Hemophagocytic lymphohistiocytosis, familial or infection-associated.

PATHOLOGIC DESCRIPTION Atilano G. Lacson, MD The liver biopsy showed centrilobular congestion with accentuated hyperemia between central veins and loss of hepatocytes. A nonspecific portal triaditis was

seen, with the infiltrates composed mostly of CD3-positive lymphocytes. The changes were interpreted as consistent with nodular regenerative hyperplasia. The spleen weighed 1264 g. The splenic capsule was gray-purple, with no suspicious focal lesions seen on gross inspection or upon sectioning into thin slices. The cut surfaces were beefy red and dry. Malphigian corpuscles were prominent, and a normal trabecular pattern was observed. Hilar lymph nodes were moderately enlarged, as were two other nodes from the mesentery. A portion of the tail of the pancreas was also submitted. Histologic examination showed splenic congestion often accentuated around the splenic nodules, many of which contained prominent germinal centers. The red pulp was replete with myeloid cells at various maturational stages. Cytologically bland histiocytes abounded (Fig 1), along with mature lymphocytes, plasma cells, and occasional megakaryocytes. No granulomas or viral cytopathic changes were noted. No parasitic organisms were identified; cytologic atypia was absent. The hilar lymph nodes showed normal lymphoid follicles surrounded by mantle and marginal zones, with prominent sinus histiocytosis; the sinusoids were packed with cytologically blandappearing histiocytes, many of which showed hemophagocytosis, predominantly erythrophagocytosis. Again, no viral cytopathic changes or malignant infiltrates were noted. Touch preparations from the surfaces of the spleen and lymph nodes revealed a striking population of large cells with eccentric ovoid nuclei and abundant cytoplasm often showing engulfed red blood cells (Fig 2). The section from the tail of the pancreas was composed of unremarkable islets of Langerhans that were surrounded by normal pancreatic acinar tissue. Aggregates of mature lymphocytes were present within the capsule and along fibrous septa. Enlarged lymph nodes, although architecturally intact, showed some depletion of lymphocytes. Prominent histi-

KOHLI-KUMAR ET AL

THE JOURNAL OF PEDIATRICS

VOLUME 140, NUMBER 5 ocytosis composed of cytologically bland erythrophagocytic histiocytes was seen within the subcapsular and intramedullary sinuses. No malignant infiltrates were seen. A depletion of CD3+ and CD20+ lymphocytes was noted in the lymph nodes but most conspicuously in the spleen. Most of the cells in the spleen were of myeloid lineage, which reacted with a monocloncal antibody against myeloid cells (Zymed, 133400). Antibody to CD68 highlighted a large histiocytic component, many of which showed hemophagocytosis of red cells and myeloid elements. There was no evidence of B-cell lineage restriction, as demonstrated by the κ and λ stains. The sinus histiocytes in both the lymph nodes and spleen were negative for S100 and CD1a antigens. At autopsy, the liver showed early veno-occlusive changes with perivenous fibrosis and phlebitis. Kupffer’s cell hyperplasia was noted, along with extensive extramedullary hematopoiesis and hemophagocytosis. Liver cell injury was apparent with collapse of the reticulin framework between central veins. Moderate intracellular and cholangiolar cholestasis were noted. Several mediastinal lymph nodes were sampled; these showed lymphocyte depletion with sinusoids packed with hemophagocytic histiocytes (Fig 3). Similar infiltrates were seen in the thymus and the bone marrow. Lymphoid infiltrates were noted around the pituitary. The left cranial nerve VII nucleus showed mild gliosis with mild neuronal loss compatible with a retrograde degeneration. No lymphohistiocytic infiltrates were seen in this area or in the rest of the central nervous system. The patient died of a severe hemorrhagic and necrotizing obstructive tracheobronchitis caused by Klebsiella oxytoca, which was discovered by bronchoscopy. At autopsy, the tracheobronchial tree was distended and obstructed by necrotic sloughed epithelial masses with distal alternating atelectases and hyperinflation. The alveolar spaces were consolidated by acute in-

Fig 3. Mediastinal lymph node showing hemophagocytosis (arrows) (hematoxylin and eosin, original magnification 400). Table II. Genetic studies in HLH

Year

Author

1984 1986

Gligenkrantz16 Kletzel17

1996 1999

Hasle18 Ohadi19

1999 1999 1999

Dufourcq20 Arico13 Stepp21

Chromosome abnormality Fragile site in chromosome 2 Double minutes, occasional loss of chromosomes 7 and 12 46,XY inv 9p23q31 or 46,XY inv 9p23q32 Gene localized to chromosome 9q21.3-22 by homozygosity mapping Chromosome 10q21-22 by linkage analysis del 22q11.2 Perforin gene mutations at 10q21-22

flammatory exudates and beginning organization.

PATHOLOGIC DISCUSSION Hemophagocytic syndrome has a wide differential diagnosis that includes an autosomal recessive form of hemophagocytic lymphohistiocytosis (HLH) known as primary or FHL.5 HLH was first described in 1952 by Farquhar and Claireaux,6 who called it familial hemophagocytic reticulosis, in a

pair of sibling infants who had irritability, anorexia, fever, hepatosplenomegaly, progressive pancytopenia, and terminal jaundice. Prominent hemophagocytosis was observed in the bone marrow, liver, spleen, and lymph nodes on autopsy examinations (Farquhar6). Additional observations in several families led to the conclusion that this is an autosomal-recessive disorder.7 Risdall et al8 in 1979 described a condition that mimics the clinical, laboratory, and histologic findings in HLH in 19 patients, 13 of whom had a documented viral infection most commonly of the herpes group, prompt611

KOHLI-KUMAR ET AL

ing them to name this subset of patients as having viral-associated hemophagocytic syndrome (VAHS). EBV accounts for many of these cases (EBV-VAHS). This can and must be distinguished from non EBV-VAHS by morphologic and biologic markers because of biologic differences; non–EBV-VAHS appears to have a better prognosis.9 Several reports have described the same syndrome among patients with bacterial infections, parasitic infestations, and various malignancies.10 The pathogenesis is assumed to be because of an abnormal production of cytokines including phagocytosis-inducing factor produced by CD4+ T cells, interferon-γ, which may contribute to myelosuppression, IL-2 deficiency, or increased soluble IL-2 receptors, which block the normal immune response leading to an immunodeficient state. In addition, elevations of IL-6 and tumor necrosis factor-α are seen regularly.11 Pathologically, there is no difference between the inherited disorder and that which can be ascribed to other conditions as mentioned above. These pathologic changes consist of widespread infiltrates of nonmalignant lymphocytes and macrophages in liver, spleen, central nervous system, lymph nodes, and bone marrow. The liver almost always shows a pattern of chronic persistent hepatitis with lymphocytic infiltrates in the portal tracts along with Kupffer’s cell hyperplasia, which may or may not exhibit hemophagocytosis. In addition, the spleen may show hemosiderosis and fibrosis. Some conditions may induce histologic changes that could suggest the diagnosis; for instance, in EBV-VAHS, the lymph nodes and spleen may show many immunoblasts and nonsuppurative necrosis. The bone marrow may show large granular lymphocytes in T/natural killer cell proliferation-related HLH. Protozoan infections may be demonstrated in the blood or biopsies of appropriate tissues. In an autopsy study of 22 patients with apparent primary HLH, a startlingly low incidence of hemophagocytic cells was seen in the bone marrow.12 This ob612

THE JOURNAL OF PEDIATRICS MAY 2002 servation was also reported in the first study of patients in the International Registry13; thus, the recommendation that repeated marrow aspirates and/or fine needle aspiration of the liver or spleen may assist in establishing the diagnosis, once bleeding diathesis is corrected. There appears to be no distinction between primary HLH and EBV-associated HLH either pathologically or prognostically; the latter is dismal enough that these conditions require prompt intensive immunomodulation therapy up to and including compatible bone marrow transplantation,10 the only known curative procedure to date. A number of primary cases may be difficult to prove or distinguish from EBVVAHS because the former can often be triggered by EBV infection itself. The remitting nature of the hepatosplenomegaly in this case is puzzling and could be attributed to a self-limited bout of immune stimulation. At least two instances of relapsing HLH are recorded in the literature. One of these is associated with lysinuric protein intolerance described in four patients14 and the other in an apparently immunocompetent patient.15 The latter appeared to have responded to steroid therapy for each episode of hemophagocytosis. Genetic studies have been few (Table II)16-21 because this is a rare disorder. No consistent single gene abnormality for primary HLH has been isolated thus far, and it may be found ultimately to have a heterogeneous genetic origin, with ethnic differences.19

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

Anatomic Diagnoses Hemophagocytic lymphohistiocytosis, familial inheritance unproven; necrotizing tracheobronchitis secondary to Klebsiella oxytoca.

12.

13.

REFERENCES 1. Penchansky L, Browarsky E, Gilbert Barness E. Hematopoietic system. In: Gilbert Barness E, editor. Potter’s

14.

pathology of the fetus and infant. St Louis (MO): Mosby; 1997. p. 975. Anderson VM, Good RA. The thymus, spleen, lymphoid tissues and immunodeficiency disorders. In: Gilbert Barness E, editor. Potter’s pathology of the fetus and infant. St Louis (MO): Mosby; 1997. p. 1018. Hong R, Gilbert EF. Reactive hemophagocytic syndrome. Pediatr Pathol 1985;3:129. Henter JI, Elinder G, Ost A. Diagnostic guidelines for hemophagocytic lymphohistiocytosis. Semin Oncol 1991; 18:29-33. Henter JI, Arico M, Elinder G, Imashuku S, Janka G. Familial hemophagocytic lymphohistiocytosis: primary hemophagocytic lymphohistiocytosis. Hematol Oncol Clin North Am 1998;12:417-33. Farquhar JW, Claireaux AE. Familial hemophagocytic reticulosis. Arch Dis Child 1952;27:519-25. Hallahan AR, Carpenter PA, O’Gorman-Hughes DW, Vowels MR, Marshall GM. Haemophagocytic lymphohistiocytosis in children. J Paediatr Child Health 1999;35:55-9. Risdall RJ, McKenna RW, Nesbit ME, Krivit W, Balfour HH Jr, Simmons RL, et al. Virus-associated hemophagocytic syndrome: a benign histiocytic proliferation distinct from malignant histiocytosis. Cancer 1979;44:993. Janka G, Imashuku S, Elinder G, Schneider M, Henter JI. Infection- and malignancy-associated hemophagocytic syndromes: secondary hemophagocytic lymphohistiocytosis. Hematol Oncol Clin North Am 1998;12:435-44. Imashuku S. Differential diagnosis of hemophagocytic syndrome: underlying disorders and selection of the most effective treatment. Int J Hematol 1997; 66:135-51. Imashuku S, Hibi S, Tabata Y, Sako M, Hirayama K, Sakazaki H, et al. Biomarker and morphologic characteristics of Epstein-Barr virus-related hemophagocytic lymphohistiocytosis. Med Pediatr Oncol 1998;31:131-7. Ost A, Nilsson-Ardnor S, Henter JI. Autopsy findings in 27 children with haemophagocytic lymphohistiocytosis. Histopathology 1998;32:310-6. Arico M, Janka G, Fischer A, Henter JI, Blanche S, Elinder G, et al. Hemophagocytic lymphohistiocytosis: report of 122 children from the International Registry: FHL Study Group of the Histiocyte Society. Leukemia 1996;10:197-203. Duval M, Fenneteau O, Doireau V, Faye A, Emilie D, Yotnda P, et al. Inter-

KOHLI-KUMAR ET AL

THE JOURNAL OF PEDIATRICS

VOLUME 140, NUMBER 5 mittent hemophagocytic lymphohistiocytosis is a regular feature of lysinuric protein intolerance. J Pediatr 1999;134: 236-9. 15. Ohno T, Hishizawa M, Hada S, Sugiyama T, Furukawa H. Two separate episodes of hemophagocytic syndrome at a two-year interval in an apparently immunocompetent male. Int J Hematol 1999;69:101-4. 16. Gilgenkrantz S, Gregoire MJ, Chery M, Bordigoni P, Olive D. Site fragile sur le chromosome 2 (q11) dans un cas de lymphohistiocytose familiale. J Genet Hum 1984;32:209-19.

17. Kletzel M, Gollin SM, Gloster ES, Jimenez JF, Golladay ES, Berry DH. Chromosome abnormalities in familial hemophagocytic lymphohistiocytosis. Cancer 1986;57: 2153-7. 18. Hasle H, Brandt C, Kerndrup G, Kjeldsen E, Sorensen AG. Haemophagocytic lymphohistiocytosis associated with constitutional inversion of chromosome 9. Br J Haematol 1996; 93:808-9. 19. Ohadi M, Lalloz MR, Sham P, Zhao J, Dearlove AM, Shiach C, et al. Localization of a gene for familial hemo-

phagocytic lymphohistiocytosis at chromosome 9q21.3-22 by homozygosity mapping. Am J Hum Genet 1999;64:165-71. 20. Dufourcq-Lagelouse R, Jabado N, LeDeist F, Stephan JL, Souillet G, Bruin M, et al. Linkage of familial hemophagocytic lymphohistiocytosis to 10q21-22 and evidence for heterogeneity. Am J Hum Genet 1999; 64:172-9. 21. Stepp SE, Dufourq-Lagelouse R, LeDeist F, Bhawan S, Certain S, Mathew PA, et al. Perforin gene defects in familial hemophagocytic hymphohistiocytosis. Science 1999;286:1957-9.

613