Hodgkin's lymphoma and its association with EBV and HIV infection.

Hodgkin's lymphoma (HL) constitutes a clonal expansion of what appears to be malignant B cells. Viruses are involved in its pathogenesis, such as the Epstein-Barr virus (EBV) and human immunodeficiency virus (HIV). Since these viral infections have been shown to play key roles in the pathogenesis of HL, countries with a prevalence of HIV and EBV represent interesting population targets to study the pathogenesis of HL, linking the evolution of the disease with viral infections. Usually, patients present with late stage disease often involving the bone marrow at the time of diagnosis. The present paper discusses the role of viral infection in African countries, as HL is considered to be a malignant disease characterized by an inflammatory reaction to an aberrant B cell clone that is well known as the Reed-Sternberg cell (HRS).

Burkitt's Lymphoma and B-Cell Lymphoma Unclassifiable With Features Intermediate Between Diffuse Large B-Cell Lymphoma and Burkitt's Lymphoma in Patients With HIV: Outcomes in a South African Public Hospital.

PURPOSE: Burkitt's lymphoma (BL) is a common HIV-associated lymphoma in South Africa. B-cell lymphoma unclassifiable with features intermediate between diffuse large B-cell lymphoma and Burkitt's lymphoma (BL/DLBCL) also occurs in HIV infection. Outcomes of HIV-infected patients with BL or BL/DLBCL in a resource-constrained setting are not defined. METHODS: We performed a retrospective study of HIV-positive patients with BL or BL/DLBCL treated from 2004 to 2012 with curative intent at a publically funded academic medical center in South Africa. Differences between BL and BL/DLBCL, survival outcomes, and factors associated with survival were analyzed. RESULTS: There were 35 patients with either HIV-associated BL (24) or BL/DLBCL (11) who met study criteria. Median CD4+ T-lymphocyte count at lymphoma diagnosis was 188 cells/µL (range, 10 to 535 cells/µL). Patients with BL/DLBCL were significantly older and had less bone marrow involvement and lower baseline serum lactase dehydrogenase than patients with BL. Eighty-nine percent of patients presented with advanced disease, and 25% had baseline CNS involvement. Chemotherapy regimens consisted of cytoreduction with low-dose cyclophosphamide, vincristine, and prednisone followed by induction with vincristine, methotrexate, cyclophosphamide, doxorubicin and prednisone (LMB 86; 57%); hyperfractionated cyclophosphamide, vincristine, doxorubicin, dexamethasone, methotrexate, and cytarabine (hyper-CVAD; 20%); cyclophosphamide, doxorubicin, vincristine, and prednisone and high-dose methotrexate with leucovorin rescue on day 10 with accompanying prophylactic IT chemotherapy (Stanford regimen; 14%); and cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP-like; 9%) regimens. Twenty-three patients received CNS treatment or prophylaxis, and 31 received concurrent combination antiretroviral therapy. Two-year overall survival was 38% (95% CI, 22% to 54%) and 2-year event-free survival was 23% (95% CI, 11% to 38%), with no difference between histologic subtypes. Common causes of death were infection (41%) and CNS disease progression or systemic relapse (41%). CONCLUSION: Cure of HIV-associated BL and BL/DLBCL with intensive regimens is possible in resource-limited settings, but lower toxicity regimens, improved CNS prophylaxis, and increased resources for supportive care are required.

A 54-year-old man referred with nonresolving pneumonia.

A 54-year-old man was referred with nonresolving pneumonia. He had been treated for community-acquired pneumonia 6 weeks earlier. He reported grade 2 dyspnea, malaise, and a nonproductive cough. He had also experienced three episodes of minimal hemoptysis but denied weight loss, fever, or any other constitutional symptoms. He was a nonsmoker and was being treated for dyslipidemia.

Microscopic colitis as a missed cause of chronic diarrhea.

AIM: To determine the prevalence of increased intraepithelial lymphocytes, using immunohistochemistry in patients with normal colonoscopy and near normal biopsy. METHODS: We retrospectively reviewed all non-malignant colon mucosal biopsies between 2005 and 2007, reported as normal, chronic inflammation or melanosis coli in patients who were undergoing routine colonoscopy. Immunohistochemistry using CD3 was performed on all mucosal biopsies and an intraepithelial lymphocyte count (IEL) was determined. Cases with an IEL count of ≥ 20 IELs per 100 surface epithelial cells were correlated with demographic, clinical and follow-up data. A further subgroup was evaluated for lymphocytic colitis. RESULTS: Twenty (8.3%) of 241 cases revealed an IEL count ≥ 20. Six (2.5%) patients were identified as having lymphocytic colitis (P < 0.001), of whom, five were missed on initial evaluation (P = 0.01). Four of these five patients were labeled with diarrhea-predominant irritable bowel syndrome (IBS). On follow-up, three of the remaining 20 cases were diagnosed with malignancy (renal cell carcinoma and myelodysplastic syndrome) and one had an unknown primary tumor with multiple liver metastases. Two cases of collagenous colitis with an IEL count < 10 were included in this study. Increased IELs were not confined to patients with diarrhea as a primary presenting symptom, but were also present in patients with abdominal pain (n = 7), constipation (n = 3) and loss of weight (n = 1). CONCLUSION: Immunohistochemistry using CD3 is of value in identifying and quantifying IELs for the presence of microscopic colitis in patients with diarrhea-predominant IBS.