Sea-blue histiocytosis secondary to Niemann-Pick disease type B: a case report.

Sea-blue histiocytosis is a morphological finding that can be associated both with acquired conditions of increased cellular turnover and inborn errors of lipid metabolism. We report a rare case of sea-blue histiocytosis associated with a mild phenotype of Niemann-Pick disease (NPD) type B in a 44-year-old man who presented with splenomegaly and mild thrombocytopenia. Diagnosis was guided by the morphological finding in bone marrow smears of foamy and sea-blue histiocytes and confirmed by the measurement of acid lysosomal sphingomyelinase activity below normal values. NPD type B is a rare inborn error of metabolism, with a benign course and prognosis, while types A and C are always associated with severe neurological involvement. In our patient diagnosis was confirmed by the specific enzyme assay of leukocytes (deficiency in sphingomyelinase activity). This is a simple and noninvasive method that is useful whenever clinical and morphological finding are relevant, and a primary hematological disorder has been ruled out.

Interferon therapy in HCV-positive mixed cryoglobulinaemia: viral and host factors contributing to efficacy of the therapy.

BACKGROUND: In a previous paper, we reported on the short-term efficacy of alpha-interferon in the treatment of hepatitis C virus positive mixed cryoglobulinaemia. AIMS: We investigated the long-term effects of therapy in a larger group of patients, and the viral and host factors able to influence the response to treatment. METHODS: In 27 females and 15 males (mean age 54.8 +/- 9.1 years) affected by mixed cryoglobulinaemia, bone marrow biopsy and phenotyping of marrow cells were performed before treatment and at the end of follow-up. A liver biopsy was obtained from patients showing biochemical signs of chronic liver disease. The presence of hepatitis C virus was assessed by detection of serum anti-hepatitis C virus antibodies, and hepatitis C virus-RNA. The treatment schedule was 3 million units of recombinant interferon alpha-2b three times a week for one year. Follow-up lasted for 1 year after the end of treatment. The response was classified as follows: 1) Complete response: Disappearance of the cryocrit (or reduction of more than 50%) and of all clinical manifestations of the disease. 2) Partial response: Disappearance of all clinical signs of the disease, but reduction of cryocrit of less than 50%. 3) Minor response: Reduction of cryocrit of less than 20% associated with the disappearance of one or more (but not all) signs of vasculitis. RESULTS: Anti-hepatitis C virus antibodies were present in 41 (95%) patients, and hepatitis C virus-RNA was detectable in all cases. Before therapy, marrow histology showed a massive monomorphous infiltration by plasmacytoid lymphocytes indicating the presence of low-grade non-Hodgkin lymphoma in 7 cases (16.6%). After therapy, 13 (31%) patients achieved a complete response, 23 patients (55%) a partial response, and 6 patients (14%) a minor response. Seven of the responders and all patients showing partial or minor responses relapsed a few months after withdrawal of therapy. At the end of the follow-up, only 6 patients had obtained complete remission. Bone marrow examination showed that B-lymphocytic monoclonal infiltrate had disappeared in 3 long-term responders. No difference was found between responders and non-responders/relapsers in terms of age, sex, duration of the disease, severity of symptoms, liver function tests, rheumatoid factor or complement levels, while the lack of response was associated with the presence of genotype 1b, liver cirrhosis, and high cryoglobulin level. CONCLUSIONS: Mixed cryoglobulinaemia is associated with a high prevalence of B-cell lymphomas. Alpha-Interferon is an effective agent for the treatment of this disease and seems able to determine regression of the lymphoproliferative disorder. The hepatitis C virus genotype and cryoglobulin level are the most important predictive factors of response to therapy.

Eosinophilic peroxidase deficiency. Cytochemical and ultrastructural characterization of 21 new cases.

Morphologic, instrumental (flow cytometric), cytochemical, ultrastructural, and chromosomal studies were performed in 21 cases of eosinophilic peroxidase deficiency that were observed in an area of northeastern Italy in the last 5 years. It was found that eosinophilic peroxidase deficiency occurred with a frequency of 1 case in 14,000 complete blood counts yearly, and thus is less rare than previously thought. Eosinophils appeared morphologically normal when examined using the light microscope, but ultrastructural study disclosed several aspecific granule alterations. In the first family studied, members with partial and total deficit were identified; in all the other cases, the enzyme deficit was total (negative cytochemical reactions and absence of dimethylaminoazobenzene-positive specific granules at the electron microscope), isolated (a single affected member in each family examined), and stable (persistent at long-term follow-up). Eosinophilic peroxidase deficiency was not correlatable with any particular disease, although a nonsignificant association with allergic-type conditions was observed. Studies are in progress to examine the modality of the defect's genetic transmission, as well as problems related to possible functional alterations and correlated clinical consequences.

Time-related shape control modifications during erythrocyte storage with additive solutions.

To obtain more detailed information on the reversibility of shape alterations in blood bank stored erythrocytes, we have studied shape recovery after chemical crenation and rheological properties in 8 PAGGS-sorbitol preserved erythrocyte concentrates during a five week storage period under blood bank conditions. Our results show that red cell capability to regain a normal discoid shape after chemical crenation decreases during storage but is not lost over a five week period. Moreover there is a significant but weak correlation between red cell ATP content and both shape recovery capability and viscosity. Our results confirm suspicious that red cell shape perturbations following blood bank storage are widely reversible. Two different mechanisms may be involved in reducing shape recovery capability during storage, namely an ATP-dependent mechanism and an energy-independent one. The energy dependent mechanism may be preserved by the previous addition of solutions which maintain higher energy levels during storage.