Acquired amegakaryocytic thrombocytopenia previously diagnosed as idiopathic thrombocytopenic purpura in a patient with hepatitis C virus infection.

We report the first case of a patient with hepatitis C virus (HCV) infection and idiopathic thrombocytopenic purpura (ITP), who later developed acquired amegakaryocytic thrombocytopenia (AAMT), with autoantibodies to the thrombopoietin (TPO) receptor (c-Mpl). A 64-year-old woman, with chronic hepatitis C, developed severe thrombocytopenia and was diagnosed with ITP. She died of liver failure. Autopsy revealed cirrhosis and liver carcinoma. In the bone marrow, a marked reduction in the number of megakaryocytes was observed, while other cell lineages were preserved. Therefore, she was diagnosed with AAMT. Additionally, autoantibodies to c-Mpl were detected in her serum. Autoantibodies to c-Mpl are one of the causes of AAMT, acting through inhibition of TPO function, megakaryocytic maturation, and platelet formation. HCV infection induces several autoantibodies. HCV infection might also induce autoantibodies to c-Mpl, resulting in the development of AAMT. This mechanism may be one of the causes of thrombocytopenia in patients with HCV infection.

Drug-induced immune thrombocytopenia: incidence, clinical features, laboratory testing, and pathogenic mechanisms.

Drug-induced immune thrombocytopenia (DIIT) is a relatively uncommon adverse reaction caused by drug-dependent antibodies (DDAbs) that react with platelet membrane glycoproteins only when the implicated drug is present. Although more than 100 drugs have been associated with causing DIIT, recent reviews of available data show that carbamazepine, eptifibatide, ibuprofen, quinidine, quinine, oxaliplatin, rifampin, sulfamethoxazole, trimethoprim, and vancomycin are probably the most frequently implicated. Patients with DIIT typically present with petechiae, bruising, and epistaxis caused by an acute, severe drop in platelet count (often to <20,000 platelets/pL). Diagnosis of DIIT is complicated by its similarity to other non-drug-induced immune thrombocytopenias, including autoimmune thrombocytopenia, posttransfusion purpura, and platelet transfusion refractoriness, and must be differentiated by temporal association of exposure to a candidate drug with an acute, severe drop in platelet count. Treatment consists of immediate withdrawal of the implicated drug. Criteria for strong evidence of DIIT include (1) exposure to candidate drug-preceded thrombocytopenia; (2) sustained normal platelet levels after discontinuing candidate drug; (3) candidate drug was only drug used before onset of thrombocytopenia or other drugs were continued or reintroduced after resolution of thrombocytopenia, and other causes for thrombocytopenia were excluded; and (4) reexposure to the candidate drug resulted in recurrent thrombocytopenia. Flow cytometry testing for DDAbs can be useful in confirmation of a clinical diagnosis, and monoclonal antibody enzyme-linked immunosorbent assay testing can be used to determine the platelet glycoprotein target(s), usually GPIIb/IIIa or GPIb/IX/V, but testing is not widely available. Several pathogenic mechanisms for DIIT have been proposed, including hapten, autoantibody, neoepitope, drug-specific, and quinine-type drug mechanisms. A recent proposal suggests weakly reactive platelet autoantibodies that develop greatly increased affinity for platelet glycoprotein epitopes through bridging interactions facilitated by the drug is a possible mechanism for the formation and reactivity of quinine- type drug antibodies.

Nonclinical Safety Profile of BMS-986001, a Nucleoside Transcriptase Inhibitor for Combination Retroviral Therapy.

Nucleoside reverse transcriptase inhibitors (NRTIs)/nucleotide reverse transcriptase inhibitors are key components of combination antiretroviral therapy for HIV infection. First-generation NRTIs are associated with mitochondrial toxicity in patients, mainly due to inhibition of human DNA polymerase γ (hDNA polγ) that manifests as adverse events such as lipodystrophy, lactic acidosis, myopathy, cardiomyopathy, or nephropathy in patients. In chronic nonclinical studies in rodents and nonrodents, eukaryotic (host) mitochondrial toxicity manifests as some drug-specific toxicities similar to human toxicity. BMS-986001, a novel thymidine analog with minimal hDNA polγ inhibition, has demonstrated antiretroviral activity in early clinical studies. The primary toxicity of BMS-986001 in rats and monkeys is bone marrow dyserythropoiesis with associated decreases in red blood cell mass. Additionally, at high doses, severe platelet reductions accompanied by cutaneous petechiae began during weeks 8 and 11 in 3 of 60 monkeys in chronic toxicity studies. In a 6-month study, platelet reductions required euthanasia of the 2 affected monkeys (300 mg/kg/d) at week 14, but with dose reduction (200 mg/kg/d) remaining monkeys had no platelet changes. One affected monkey (200 mg/kg/d) in a 9-month study completed dosing and its platelet counts recovered during a 1-month recovery. Formation of platelet-bound immunoglobulin in the presence of BMS-986001, together with rapid and complete platelet recovery in the absence of BMS-986001, suggested that platelet decreases in monkeys may be immune mediated. No findings indicative of mitochondrial toxicity were observed in rats or monkeys given BMS-986001, suggesting an improved safety profile compared to marketed NRTI or tenofovir disoproxil fumarate.

Platelet antibodies, activated platelets and serum leptin in childhood immune thrombocytopenic purpura.

BACKGROUND/AIM: The aim of this study was to evaluate the levels of platelet-associated antibodies (PAIgG and PAIgM), activated platelets and serum leptin in children with acute immune thrombocytopenic purpura (ITP). METHODS: The study included 40 patients with ITP and 40 healthy age- and sex-matched controls. PAIgG, PAIgM and activated platelet levels were estimated by flow cytometry, and serum leptin levels were estimated by ELISA. RESULTS: Activated platelets and serum leptin were significantly higher in the ITP patients than in the controls. The percentage and mean fluorescence intensity of PAIgG and PAIgM staining were significantly higher in the patients than in the controls. Serum leptin and activated platelet levels in patients with thrombocytopenia of brief duration were significantly lower than those in patients with thrombocytopenia of prolonged duration. The levels of activated platelets, serum leptin and PAIgG were positively correlated, and the levels of serum leptin, activated platelets and platelet counts were negatively correlated. CONCLUSION: The increased levels of activated platelets, serum leptin and platelet-associated antibodies in children with acute ITP suggest that these factors could play a role in ITP pathogenesis. Additionally, activated platelets and serum leptin could have prognostic significance in paediatric acute ITP.

Laboratory testing for platelet antibodies.

Laboratory testing for immune-mediated thrombocytopenias involves identification and classification of antibodies present in patient sera or attached to patient platelets. This article summarizes the available types of platelet antibody testing and applications in disorders such as neonatal alloimmune thrombocytopenia, post-transfusion purpura, multiple platelet transfusion refractoriness, immune thrombocytopenia, and drug-induced thrombocytopenia.

TGFß(1) and sCTLA-4 levels are increased in eltrombopag-exposed patients with ITP.

Some thrombopoietin receptor-agonists (TPR-As) have been developed and shown to be highly effective in the treatment of immune thrombocytopenic purpura (ITP). Soluble cytotoxic T-lymphocyte-associated antigen 4 (sCTLA-4) can modulate and terminate the immune response. Several reports have shown that sCTLA-4 levels are elevated in patients with some autoimmune disorders. However, sCTLA-4 levels have not previously been investigated in TPR-A exposed patients with ITP. We investigated the levels of transforming growth factor (TGF) ß(1) and sCTLA-4 in ITP patients to determine the clinical association with TGFß(1) and sCTLA-4 in TPR-A-exposed patients with ITP. Thirty-seven ITP patients were divided into 2 groups (TPR-A-exposed: 13 patients; unexposed: 24 patients). Doses of eltrombopag ranging from 12.5mg to 50mg were administered daily, and biochemical data obtained before and after eltrombopag administration were compared. Eltrombopag therapy significantly increased sCTLA-4 and TGFß(1) levels relative to baseline in patients with ITP. In addition, plasma TGFß(1) was positively correlated with platelet counts and sCTLA-4 in patients with ITP in the eltrombopag-exposed group. However, no significant change in the detection rate for anti-glycoprotein antibody was observed before and 24 weeks after eltrombopag treatment. These results suggest that eltrombopag can partially modulate some immune responses by TGFß(1) and sCTLA-4, but it does not induce immune tolerance by 24 weeks after treatment.

Severe haematological complications during treatment with natalizumab.

The safety profile of natalizumab has been widely discussed due to several cases of progressive multifocal leukoencephalopathy, reported worldwide. Since the launch of natalizumab, 32 patients have been treated at our centre. In this context, we describe two cases (6.25%), one of immune-mediated acute haemolytic anaemia (IAHA) and another of immune thrombocytopenic purpura during treatment with natalizumab. The temporal relationship between drug administration and the nature of the haematological complications, confirmed with the serological findings in the case of the IAHA, suggests that natalizumab is the most probable cause for these adverse events. Although very uncommon, the haematological complications are severe enough to justify a close and careful monitoring for all patients with multiple sclerosis treated with an immunosuppressant treatment.

Efficacy of rituximab in immune thrombocytopenic purpura: a retrospective survey.

We conducted a retrospective survey to assess prescription practice, response rates to rituximab, and the predictive indicators for a response to rituximab therapy in patients with primary or secondary immune thrombocytopenic purpura (ITP). Data were collected retrospectively from 40 consecutive patients with ITP attending our hospital: 29 (72.5%) had primary ITP and 11 (27.5%) had secondary ITP. Rituximab was given either as four weekly injections (375 mg/m(2)) or two injections of 1,000 mg given 2 weeks apart in 30 and 10 patients, respectively. The primary objective was to evaluate overall (OR) and complete response (CR) to rituximab therapy for ITP. OR was excellent and rapid and similar when secondary ITP was excluded from the analysis: OR was achieved in 28 (71.8%) patients and CR in 22 (56.4%). But, at >6 months, of the 28 responders, only 10 of 22 of the evaluable responses (45.5%) were sustained. In addition, except for the nonsignificant occurrence of antinuclear antibodies, no clinical or biological factors were predictive for OR or CR after the rituximab therapy. Twelve patients received a second course of rituximab. Overall, rituximab therapy achieved a response in two thirds of the patients, but the responders exhibited a high rate of early relapses, with no obvious difference according to the regimen of administration or rituximab dose.

Favorable response of chronic refractory immune thrombocytopenic purpura to mesenchymal stem cells.

Seven patients with chronic refractory immune thrombocytopenic purpura (ITP) received adipose tissue-derived mesenchymal stem cells (AMSC) from haplo-identical family donors. The AMSC dose was 2.0×10(6)/kg. No side effects were noted after the AMSC infusions. Overall responses were reached in all patients and sustained response rate was 57.1% (4/7). The serum levels of transforming growth factor ß1 (TGF-ß1), interleukin (IL)-4, and IL-10 were significantly elevated, whereas those of interferon-γ (IFN-γ) and IL-2 were significantly decreased after AMSC administration, compared with those in the patients with active ITP. During follow-up, the cytokine profiles in patients maintaining sustained response remained stable compared with the post-treatment level, but IFN-γ and IL-2 levels were significantly increased, and those of TGF-ß1, IL-4, and IL-10 were significantly reduced again in relapsed patients. AMSC therapy seems to represent reasonable salvage treatment in severe, chronic refractory ITP by causing a shift in the Th1/Th2 cytokine balance to the same levels as normal controls.

Candida albicans-induced chronic thrombocytopenic purpura.

We present 2 patients with chronic immune thrombocytopenic purpura (ITP) secondary to Candida albicans infection. Neither patient responded to standard ITP therapy including splenectomy. Appropriate antifungal treatment of the C. albicans infection was followed by sustained improvement in platelet count in both patients. To our knowledge, this is the first report of ITP in association with C. albicans infection.

Multiple symmetric lipomatosis.

BACKGROUND: Multiple symmetric lipomatosis (MSL) is a relatively uncommon entity of unknown etiology characterized by symmetrically subcutaneous accumulation of nonencapsulated adipose tissue. Approximately 200 to 300 cases have been published. OBJECTIVES: The aims of this article are to report the case of a 58-year-old Brazilian patient with MSL and provide a comprehensive overview of the current concepts concerning this disease. METHODS: Our search yielded 28 articles on MSL, including case reports and reviews of the literature. RESULTS: MSL predominantly affects Mediterranean males with a history of chronic alcohol abuse. It is usually asymptomatic and may be associated with diabetes mellitus, hyperlipidemia, hyperuricemia, macrocytic anemia, and oral cancer. Surgical resection is the best treatment option. CONCLUSION: The case reported is a classic presentation of MSL; however, it is particularly uncommon owing to the association with immune thrombocytopenic purpura. This association has been described only once in the medical literature.

[Protocol for the study and treatment of immune thrombocytopenic purpura (ITP). ITP-2010]. / Protocolo de estudio y tratamiento de la trombocitopenia inmune primaria (PTI-2010).

Primary immune thrombocytopenia (ITP), formerly known as immune thrombocytopenic purpura, is a disease in which clinical and therapeutic management has always been controversial. The ITP working group of the Spanish Society of Paediatric Haematology and Oncology has updated its guidelines for diagnosis and treatment of ITP in children based on current guidelines, literature review, clinical trials and member consensus. The primary objective was to lessen clinical variability in diagnostic and therapeutic procedures in order to obtain best clinical results with minimal adverse events and good quality of life.

Reviewed diagnosis of primary and secondary immune thrombocytopenic purpura in 79 adult patients hospitalized in 2000-2002.

Despite the accepted distinction between primary and secondary immune thrombocytopenic purpura (ITP), a systematic analysis of the incidence of secondary ITP is not available. The present study was aimed at verifying the frequency and, consequently, the approximate rates of prevalence and incidence of secondary ITP and analysing its clinical and laboratory characteristics in patients needing ordinary hospital treatment for ITP. The study was based on 79 consecutive, adult ITP patients admitted to three Italian hospitals in 2000-2002. Using data collected in a previous study on the appropriateness of hospital management of ITP, we evaluated the frequency of secondary ITP, with the diagnosis formulated on the basis of new acquisitions, derived its rates of prevalence and incidence, and examined the available clinical and laboratory parameters. At our case review, a diagnosis of secondary ITP could be formulated in 38% of the 79 patients. This frequency was significantly higher than that determined at the time the patients were discharged from hospital (13.9%) (P = 0.000). The derived rates of prevalence and incidence of secondary ITP in the general population were, respectively, 2.3 and 1.23 per 100 000 inhabitants per year. In comparison with patients with primary ITP, those with a secondary form more frequently had spleen enlargement (P = 0.000), hepatomegaly (P = 0.001) and lower haemoglobin values (P = 0.005). The high frequency of secondary ITP must be mainly attributed to the currently available knowledge about the nature of some forms of ITP. Particular contributors to the high frequency were cases secondary to infections and those observed in patients who had undergone bone marrow or solid organ transplantation. Some clinical and laboratory alterations appear to be more frequent in secondary ITP than in primary ITP. However, the importance that the identification of particular forms of ITP, such as those secondary to Helicobacter pylori or hepatitis C virus infections, has on the choice of treatment suggests that these conditions must be ascertained independently of the presence or absence of clinical and laboratory alterations.

Immune thrombocytopenic purpura at the diagnosis of Hodgkin disease.

We describe the case of a 76-year-old male presenting a thrombocytopenia at the diagnosis of Hodgkin disease. Basing on bone marrow biopsy and evolution, we diagnosed an immune thrombocytopenia and treated with intravenous gammaglobulins. The platelet count normalized in a few days under this therapy. Immune thrombocytopenia purpura (ITP) is a rare complication of Hodgkin disease (HD). It seems to be due to the production of antibodies directed against platelet membrane proteins. The patient's and the lymphoma's characteristics are not predictive for it to happen. The evolution of HD is also not influenced by its occurrence. Various treatments (including corticoids and immunomodulating agents) have been tried with different efficiencies.

A case of nocardiasis complicated with meningitis in a patient with immune thrombocytopenic purpura.

Nocardia infection is a well recognized complication of the immunocompromised hosts. It is mostly a primary pulmonary infection, which may disseminate to other organs. The central nervous system (CNS) involvement of nocardiosis is usually manifested as brain abscesses. We report a 25-year-old male patient who presented with nocardial pneumonia and meningitis without brain abscess. He was diagnosed as immune thrombocytopenic purpura and methyl prednisolone was started 5 weeks previously. Nocardia spp. was obtained from his cerebrospinal fluid culture, but he died at the 7th day of intensive care. Nocardia meningitis is a rare manifestation of systemic disease. Nocardia meningitis should be considered in the differential diagnosis of meningitis with the coexisting nodular pulmonary lesions in the immunocompromised patient and medications other than co-trimoxazole may be required.