Bcl-6 protein expression by follicle center lymphomas. A marker for differentiating follicle center lymphomas from other low-grade lymphoproliferative disorders.

Low-grade lymphoproliferative disorders are a heterogeneous group of lymphoid neoplasms with wide variation in histologic features, immunologic phenotype, and molecular abnormalities. Subclassification of these disorders with small lymphocytic proliferation may be difficult on the basis of morphologic findings alone. The bcl-6 gene, originally cloned from a tumor with 3q27 translocation, is commonly expressed in large cell lymphomas. In humans, bcl-6 encodes for a Krüppel-type zinc finger protein and is believed to be important in germinal center formation. Bcl-6 protein is expressed mainly by follicle center cells and a few interfollicular T lymphocytes. We analyzed Bcl-6 expression with immunologic methods in common low-grade lymphoproliferative disorders as an aid to differentiation of tumors with follicle center origin. We analyzed Bcl-6 staining of formalin-fixed paraffin-embedded tissue from 72 indolent lymphomas including 31 grade I and II follicle center lymphomas (FCL). 13 small lymphocytic lymphomas (SLL), 12 mantle cell lymphomas (MCL), and 16 marginal zone lymphomas (MZL) including lymphomas of mucosa-associated lymphoid tissue and spleen. All of 31 FCL were positive for Bcl-6 expression. One of 13 SLL and 1 of 12 MCL were positive, whereas none of 16 MZL were positive. Bcl-6 was also detected in 5 of 5 FCL and 1 of 3 MZL but in no SLL or MCL by Western blot analysis in 14 cases with lymphoid disorders. Our study demonstrates that Bcl-6 expression is common in low-grade FCL but is rare in other indolent B-cell lymphoid disorders, and may be a useful adjunct in classification of indolent lymphomas.

Disseminated herpes simplex virus infection presenting as fever in the newborn--a lethal outcome.

The clinical course of a neonate who presented with fever and tachypnea on day 6 of life is described. He developed disseminated intravascular coagulopathy, hepatic failure, coma and expired at 14 days of age. The post mortem viral cultures from liver, adrenal and lungs were positive for HSV type 2. The fatal outcome of this case of fever, due to HSV infection, emphasizes the need for early treatment of suspicious cases of HSV infection. HSV should be considered in the differential diagnosis of the newborn with persistent fever unresponsive to antibiotics.

Pathophysiology and treatment of endometriosis.

The pathophysiology of endometriosis and its treatment are discussed. Endometriosis is a gynecological disorder characterized by the growth of the ectopic endometrium. The usual plaque looks like a small blood-filled cyst that is surrounded by a puckering scar. This tissue responds to fluctuating levels of hormones just as the normal endometrium does, and monthly bleeding of the cysts occurs followed by inflammation and scarring. Endometriosis may cause infertility, dyspareunia, dysmenorrhea, pelvic pain, and other menstrual problems. Therapy is chosen based on extent of disease, tolerance of side effects, and desire for pregnancy. Surgery is usually reserved for more extensive cases of the disease or if fertility is no longer desired. Induction of "pseudopregnancy" with estrogen-progesterone combinations has been used frequently; however, weight gain, initial exacerbation of pain, and the possibility of thromboembolism are limiting factors. Pseudomenopause, induced by danazol therapy, is an alternate method of treatment that causes a static endometrium. It offers rapid relief of symptoms to the majority of patients, and its most common side effects of weight gain and edema are reversible. Fertility rates after treatment are difficult to compare, but they appear to be similar for both hormonal therapies. Danazol has emerged as an effective alternative to the estrogen-progesterone combination treatment of endometriosis. Danazol may be prescribed before surgery to reduce lesions, following surgery to ablate any remaining lesions, or as the sole therapy for endometriosis.

Hematologic complications of heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is arguably the most significant of the drug-induced thrombocytopenias. Two main types of HIT, types I and II, are usually discussed. Type I HIT is characterized by a moderate reduction in platelet counts early in heparin therapy, usually within the first 1 to 3 days. The platelet count rarely drops below 100x10(9)/L and normalizes in spite of continued heparin therapy. Type II HIT is immunologically mediated. The definition of Type II HIT varies, but most studies require a platelet count below 100-150x 10(9)/L for no apparent reason other than heparin administration. Many patients with type II HIT suffer no morbidity. Unfortunately, a significant number, 30 to 60% or more, do develop serious thrombotic complications resulting in morbidity or mortality, including ischemic damage to limbs, central nervous system, myocardium, and lungs. Although earlier literature indicated that arterial thromboses occurred more frequently than venous, recent reports have found that venous thromboses, including deep venous thromboses, pulmonary emboli, and clotted venous catheters, have been common occurrences. In some studies, venous complications were more frequent than arterial. Most investigators have come to believe that these antibodies are largely directed against complexes formed between heparin and the tetrameric PF4. Recent studies devoted to exploring the mechanism by which these antibodies induce platelet activation and thrombosis are discussed.

Uveal metastatic carcinoma in human immunodeficiency virus infection.

We report the occurrence of uveal metastatic carcinoma in two patients with longstanding HIV infection presenting with decreased visual acuity. In the first case, a 49-year-old man with a 6-year history of HIV infection presented with a 4-5 month history of blurred vision in his right eye. In the second case, a 53-year-old man with a 5-year history of HIV infection presented with a 3-week history of distorted and blurred vision in both eyes. In both cases, a choroidal metastatic carcinoma was ultimately discovered. To our knowledge, these are the first reported cases of metastatic uveal carcinoma in individuals with HIV infection. Currently, there have been dramatic improvements in treatment for HIV infection and longer survival times of infected individuals. This fact, together with reported increased frequencies and aggressiveness of carcinomas in HIV-infected individuals will likely result in increasing occurrences of uveal metastases from primary carcinomas in HIV.