No abstract

Eight cases of isolated peripheral tuberculous lymphadenitis occurred over a 16-month period at our institution, prompting a literature review to establish the epidemiology, clinical manifestations, and current approaches to diagnosis and treatment of this disorder. It occurs most commonly in young adult women who either are immigrants from areas where tuberculous is endemic or have histories of travel that are suggestive of exposure to Mycobacterium tuberculosis. The disease is indolent and usually presents as a unilateral painless neck mass. Constitutional symptoms are rare, except in individuals infected with the human immunodeficiency virus (HIV). The results of skin testing with purified protein derivative are invariably positive. Excisional biopsy for histopathologic and microbiological evaluations provides the highest diagnostic yield, although fine needle aspiration may be useful for HIV-infected individuals and in areas of the world with a high prevalence of disease. A 6-month course of combination antituberculous therapy is adequate for disease due to susceptible organisms. This infection may be readily diagnosed if suggestive epidemiological and clinical findings lead to expeditious tissue sampling.

Characterization of persons highly exposed to human immunodeficiency virus (HIV)-1 who remain uninfected may help define protective immunity. Seventeen HIV-1-seronegative Thai female sex workers (CSWs) with epidemiologic evidence of exposure to HIV-1 were studied for humoral immune responses and phenotypic and genotypic analyses of HLA class I and CCR5 allelic profiles. Infected CSWs and low-risk HIV-1-seronegative Thai women were controls. Highly exposed, persistently seronegative (HEPS) CSWs did not differ from HIV-infected CSWs in HIV risks, condom use, or sexually transmitted diseases. Significant differences were seen in humoral immune responses: gp160-specific IgA responses were detected in cervicovaginal lavage fluids in 6 of 13 HEPS CSWs but 0 of 21 seronegative subjects. All women had wild-type CCR5. HEPS CSWs were more likely to have the HLA-B18 phenotype and genotype than were matched controls (corrected P=.018). Epidemiologic exposure to HIV-1 without apparent infection, an unusual distribution of HLA class I alleles, and HIV-1 gp160-specific IgA responses suggest a biologic basis for this phenomenon.

Human immunodeficiency virus type 1 isolates of envelope genotype E are contributing substantially to the global pandemic. These strains appear to be mosaics, with the gag gene from clade A and the envelope from clade E; the parental clade E strain has not been found. Here we report the first full genomic sequence of one such mosaic virus, isolate CM240 from Thailand. Multiple breakpoints between the two parental genotypes have been found in a CM240 virus. The entire gag-pol region and most, if not all, of the accessory genes vif, vpr, tat, rev, and vpu appear to derive from clade A. The genotype switches to E shortly after the signal peptide of the envelope and back to clade A near the middle of gp41; thus, the portion of the envelope that lies on the cytoplasmic side of the membrane appears to be principally derived not from clade E, as previously thought, but from clade A. Another small segment not belonging to any recognized clade and presumably also contributed by the parental E strain has been found in the long terminal repeat. It may be significant that the implied virion structure resembles a pseudotype virus with the matrix and core from one clade and the outer envelope from another. In the long terminal repeat, differences were observed between CM240 and other clades in the number of NF-B binding sites, the sequence of the TATA box, and the putative secondary structure of the transactivation response region stem-loop. The mosaic structure of a CM240 virion is suggestive of phenotypic differences which might have contributed to the emergence of this variant.

SEA incidence has increased more than three-fold over the past decade at a large, high-volume, academic medical center. This retrospective, case-control study identified several attributes that could inform the early recognition of this potentially highly morbid acute infection of the central nervous system.