Hemophagocytic lymphohistiocytosis as a syndrome: correlation of clinicopathological data

Bone marrow transplantation in a child with hemophagocytic lymphohistiocytosis using a less toxic conditioning regimen

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare non-neoplastic, frequently fatal disease of childhood. HLA-matched bone marrow transplantation (BMT) can bring about long-term remission and an eventual cure.

METHODS

We report on the beneficial effect of BMT in a 2-month-old male using a less intensive conditioning regimen. The regimen included busulfan at 4 mg/kg/day (total dose 16 mg/kg), etoposide at 300 mg/m2/day (total dose 900 mg/m2), and cyclophosphamide at 50 mg/kg/day (total dose 150 mg/kg). Prophylaxis for graft-vs.-host disease included methotrexate and cyclosporine.

RESULTS

An absolute neutrophil count of 500 microL was noticed on + day 12 (engraftment day). At present, i.e., 400 days after the procedure, the patient is asymptomatic, his physical examination is normal, and a slightly increased level of gamma-glutamyl-transpeptidase (GGT) and alkaline phosphatase are the only laboratory abnormalities.

CONCLUSIONS

In this case, the conditioning regimen was adequate for the eradication of the disease and allowed persistent engraftment without significant toxicity. The results in our patient suggest that a less toxic regimen is feasible and permits rapid engraftment without compromising the effectiveness of chemotherapy.

Treatment of familial erythrophagocytic lymphohistiocytosis with cyclosporine A

Familial erythrophagocytic lymphocytosis (FEL) is a rare, nonmalignant class II histiocytosis characterized by fever, irritability, hepatosplenomegaly, pancytopenia, and hemophagocytosis. Various chemotherapeutic regimens have had mixed success, with the only curative therapy being bone marrow transplantation. We report our experience with two children whose therapy with etoposide and steroids failed. They were successfully treated and had durable remissions with cyclosporine A (CSA). We propose that in FEL there may exist abnormal interactions between antigen-presenting cells and T-lymphocyte subsets, and that CSA may down-modulate this aberrant response. The use of a low-dose CSA regimen may represent a treatment option that should be further explored.

Familial haemophagocytic lymphohistiocytosis. A report of three cases with unusual lung involvement

Three cases of familial haemophagocytic lymphohistiocytosis are presented with lung infiltration by haemophagocytic histiocytes. In all patients the diagnosis was based on hepatosplenomegaly, thrombocytopenia and anaemia, abnormal increase in triglycerides, ferritin and LDH, hypofibrinogenaemia and lymphohistiocytosis with haemophagocytosis in bone marrow. Two patients died of respiratory failure due to interstitial pneumonia. In these two patients the pneumonia was obscured and misinterpreted by the pathologists. A careful re-examination revealed lymphohistiocytosis and haemophagocytic cells within the lung parenchyma. The third patient showed alveolar wall infiltration by haemophagocytic histiocytes and lymphocytes. In early childhood acute or recurrent interstitial pneumonia should prompt a search for haemophagocytic histiocytes, and familial haemophagocytic lymphohistiocytosis should be included in the differential diagnosis.

Familial hemophagocytic lymphohistiocytosis associated with disseminated T-cell lymphoma: a report of two siblings

Two siblings with evidence of disseminated T-cell lymphoma at the time of diagnosis of familial hemophagocytic lymphohistiocytosis (FHL) are reported, an association which has not been described previously. The first child with typical clinical and laboratory features of FHL died shortly after admission, before diagnosis could be established. Retrospective analysis of autoptic tissue revealed marked hemophagocytosis as well as morphological and immunohistochemical features suggestive of disseminated T-cell lymphoma. In the second child, FHL was diagnosed in time. Subsequent histologic investigation of bone marrow biopsies displayed a focal infiltration by T-cell lymphoma. DNA hybridization studies provided evidence of a monoclonal T-cell receptor beta chain gene rearrangement. Following conventional chemotherapeutic induction for FHL, the patient received an allogeneic bone marrow transplant (BMT) from a related healthy donor. Currently, 17 months after BMT, the boy is in unmaintained remission from FHL and T-cell lymphoma. The current pathogenetic concepts for FHL and a possible relationship between T-cell lymphoma and FHL are discussed.