Perforation of a retrocaecal appendix presenting clinically as a right lumbar abscess.

Presentations of acute appendicitis represent an ongoing challenge to surgeons. This case of retrocaecal perforated appendicitis presented clinically as a right lumbar abscess, with the concomitant new diagnosis of type 2 diabetes mellitus in a 66-year-old male. This case emphasises the importance of an abdominal CT scan in any patient presenting with unusual sepsis near the abdomen.     

Double vulva. A case report

Double vulva is an extremely rare congenital malformation; there are only 17 previously reported cases in the world literature. The syndrome usually consists of complete or partial duplication of the vulva, vagina, uterus, urethra, bladder and colon, with normal ovaries and kidneys and associated congenital malformations, especially of the lumbar spine. The etiology is uncertain. Mortality in the 18 cases reviewed was 35%. Diagnostic evaluation should include a careful newborn physical examination for associated congenital malformations, especially congenital heart disease, along with a radiologic survey of the lumbar spine, gastrointestinal tract and urinary system. No gynecologic surgical treatment is needed except for cosmetic reasons.     

Using serial observations to identify predictors of progression to AIDS in the Toronto Sexual Contact Study.

The Toronto Sexual Contact Study comprises a cohort of 249 male sexual contacts of men with HIV disease which has been followed every 3 months for almost 5 years. On enrollment 143 were seropositive and 16 seroconverted during the follow-up period. By 31 December 1989, 41 of the 159 seropositive cohort members had developed AIDS. Using Cox relative risk regression models, we investigated the association of a number of laboratory and clinical variables and progression to AIDS. Fixed covariate models examined laboratory variables from the enrollment visit of cohort members, with time calculated from this date. In models assessing time dependent covariates, time was calculated from the estimated date of HIV infection. In the univariate models of either fixed or time dependent covariates, many variables were significantly associated with risk of progression to AIDS (T4 cell count, T4/T8 ratio, blastogenic responses to phytohemagglutinin, concanavalin A, and pokeweed mitogen, serum IgA, appearance of p24 antigen, and the development of oral hairy leukoplakia, thrush, or herpes zoster). Appearance of persistent generalized lymphadenopathy was not associated with increased risk of progression. In the multivariate model which evaluated fixed laboratory covariates, T4/T8 ratio, IgA level, and PHA response at enrollment were significantly associated with elevated risk.(ABSTRACT TRUNCATED AT 250 WORDS)     

Diagnosing intramuscular myxoma by fine-needle aspiration: A multidisciplinary approach

The gross and microscopic appearances of aspirates from ten intramuscular myxomas are reported. The specimens were obtained from seven women and three men, ages 43 to 75, who had tumors involving the muscles of the thigh (7), upper arm (2), and forearm (1). Magnetic resonance (MR) imaging performed in six of the ten cases revealed well-defined, sharply demarcated tumors exhibiting low signal intensity relative to muscle on the T1-weighted images. The tumors were hyperintense to muscle on T2-weighted images. All aspirated tissues were clear, tenacious, and viscous. Smears contained few spindled and histiocytoid cells in an abundant mucoid background. Spindle cells demonstrated long cytoplasmic processes that in areas intertwined to form fibrillar tangles. Nuclei were oval to spindled with fine chromatin and inconspicuous nucleoli. Capillaries were sparse with simple (nonplexiform) branching. The differential diagnosis of myxoid lesions of the extremities includes benign entities such as myxoid schwannoma and neurofibroma, mesenchymal repair, and ganglion cyst, as well as malignant neoplasms such as myxoid liposarcoma, fibrosarcoma, malignant fibrous histiocytoma, and extraskeletal chondrosarcoma. The findings of this study revealed that, although the cytologic features were suggestive of intramuscular myxoma, a definitive diagnosis was often difficult, owing to scant cellularity and lack of distinctive cytologic features. The MR imaging findings may be utilized as an adjunct to the cytologic features to more confidently suggest a diagnosis of intramuscular myxoma. Diagn Cytopathol 1994;11:255–261. © 1994 Wiley-Liss, Inc.     

Adenovirus helper function activity of simian virus 40 T antigen mutants.

The SV40 large T antigen provides a helper function that permits human adenovirus yields in monkey cells to approach those obtained in human cells. The carboxy-terminus of large T antigen is involved in providing this activity. The ability of a large number of SV40 mutants affecting T antigen to enhance the growth of adenovirus type 2 in the CV-1 line of African green monkey kidney cells was examined. Mutation of those serines and threonines at the carboxy terminus which are normally phosphorylated had no effect on adenovirus helper function. A cytoplasmic T antigen was very effective in providing adenovirus helper function. Mutants that produce unstable T antigens provided helper function, but to a reduced degree. Finally, mutations in T antigen which permit it to interfere trans-dominantly with replication catalyzed by wildtype T antigen provided adenovirus helper function at wildtype levels.     

Lack of biological significance of in vitro Brugia malayi microfilarial cytotoxicity mediated by Propionibacterium acnes ("Corynebacterium parvum")-and Mycobacterium bovis BCG-activated macrophages

The effect of nonspecific activation of host macrophages by Propionibacterium acnes ("Corynebacterium parvum") or Mycobacterium bovis BCG on Brugia malayi microfilariae was determined by in vitro and in vivo studies. Intraperitoneal injection of C. parvum or BCG stimulated peritoneal exudate cells, which were toxic to microfilariae. Microfilariae were equally susceptible to damage by C57BL/6J or BALB/cJ peritoneal exudate cells. Furthermore, inhibitors of oxidative metabolism and arginine supplementation did not prevent this toxicity, suggesting that the mechanism of microfilarial damage differs from that seen with another multicellular helminth, Schistosoma mansoni. In vivo studies with both BCG and C parvum, however, did not confirm the importance of nonspecific immunity in resistance to B. malayi microfilaremia. Despite the lack of biologic relevance of this phenomenon, in vitro studies may yield important knowledge about the mechanisms of microfilarial damage.