Computed tomography in the evaluation of Brown syndrome of the superior oblique tendon sheath

Computed tomographic (CT) findings in 4 patients with superior oblique tendon sheath syndrome (congenital or acquired Brown syndrome) are described. When the inferior oblique muscle moves the eye upward, the superior oblique muscle normally relaxes, while its tendon lengthens and slides freely through the trochlea. In Brown syndrome this process is somehow restricted, which is most apparent during attempts at elevation when the eye is adducted, resulting in an apparent inferior oblique "palsy" (pseudopalsy). Brown syndrome is the most common cause of an apparent isolated limitation of the inferior oblique muscle. CT is a valuable tool in understanding the pathophysiology and management of acquired Brown syndrome, showing thickening and inflammatory changes of the reflected portion of the superior oblique tendon.     

Management of protozoal diarrhoea in HIV disease

Summary Since the first reported case of HIV infection in 1981, many HIV-seropositive patients have died as a result of diarrhoea induced by opportunistic protozoal infections: pathogens that would normally cause only a transient illness in immunocompetent individuals. The introduction of highly active antiretroviral therapy (HAART) in 1996 has been associated with a significant decline in incidence and mortality arising from infections such as cryptosporidia and microsporidia. Previously, there were no chemotherapeutic agents known to be effective in eradicating these parasites, but since the availability of HAART, the memory of the emaciated terminally ill patient with advanced AIDS suffering from refractory diarrhoea will hopefully be a thing of the past. Significant advances in the knowledge of the pathogenesis of HIV disease, earlier detection and thus treatment of the virus, and availability of improved diagnostic techniques and HAART have transformed the way HIV-associated diarrhoea is managed. In this review, we look specifically at the management of protozoa-induced diarrhoea.     

A novel basis for delta beta-thalassemia in a Chinese family

We have studied a Chinese family in which beta-thalassemia and delta beta-thalassemia were found in simple and compound heterozygous states. The delta beta-thalassemia heterozygote (the mother) had 22.3% hemoglobin F, of which 40% was G gamma and 60% A gamma; globin chain studies showed an alpha/beta + gamma ratio of 1.36. The compound heterozygote for delta beta-thalassemia and beta-thalassemia (the child) had the clinical picture of thalassemia intermedia and an alpha/beta + gamma ratio of 4.44. Gene mapping studies were performed using DNA from the affected child. Seventy kilobases of DNA in the beta- globin gene cluster starting upstream from the epsilon-globin gene and ending downstream from the beta-globin gene were mapped, and no detectable deletions or rearrangements were detected. In addition, heterozygosity was detected at multiple polymorphic restriction sites in and 3' to the beta-globin gene, which excludes the possibility of a deletion of the entire beta-globin gene cluster. This is the first example of a nondeletion delta beta-thalassemia associated with increased expression of both G gamma and A gamma genes.     

Variant von Willebrand's disease type B--revisited

Results of investigations of the factor VIII (FVIII) of a patient with an unusual variant form of von Willebrand's disease (vWD) are presented. A two-peak crossed-immunoelectrophoresis (CIE) pattern was seen when fresh plasma was electrophoresed, but the CIE pattern became normal by incubating the plasma at 37 degree C for more than 72 hr. The two peaks on CIE were separated by cryoprecipitation: the slow-moving peak precipitating and the fast-moving forms of FVIII remaining in the cryosupernate. An additional protein band was seen on multimeric analysis of FVIII. The platelet-rich plasma (PRP) from this patient did not respond to ristocetin, but agglutinated normally in response to botrocetin. Multimeric and CIE analysis of the FVIII post agglutination and 125I-FVIII binding studies to normal formalin-fixed platelets indicated that this patient's FVIII interacted normally with botrocetin but failed to interact with ristocetin. These data strongly suggest that the sites on the FVIII molecule or the multimeric forms involved for ristocetin and botrocetin are different and that the ristocetin reaction is more closely aligned to the physiologic function of FVIII.     

Pretreatment tumor mass, cell kinetics, and prognosis in multiple myeloma

One-hundred fifty patients with multiple (plasma cell) myeloma had pretreatment tumor mass staging, and 79 also had measurement of the pretreatment labeling index (LI%). There were clear differences in survival by pretreatment stage of disease. The pretreatment LI% of bone marrow plasma cells was an independent prognostic factor both in single factor and multivariate regression analyses, including myeloma stage (p less than 0.02). Other important prognostic factors (multivariate) included performance status, serum creatinine, presence of Bence Jones protein, age, and kappa/lambda subtype. A LI% of less than 1% was associated with long survival in each patient group. Patients with benign gammopathy had excellent survival and very low labeling indices. A pretreatment LI% of greater than 3% in high cell mass patients with a high total number of DNA synthesizing cells (S) conferred a very poor prognosis (p = 0.002). This subgroup of patients with high S values also had a high incidence of central nervous system relapse (27%), Bence Jones proteinuria, and elevated serum uric acid levels. We conclude that the pretreatment labeling index provides helpful prognostic information in addition to tumor mass staging.