A 1-year-old boy was vaccinated with the Oka strain of varicella just prior to the discovery of a tumor that required intensive antitumor therapy. Three months later he developed herpes zoster, which developed into chronic verrucous lesions that were refractory to treatment with acyclovir and which subsequently disseminated. DNA from a biopsy specimen of a chronic herpes-zoster lesion indicated that the Oka vaccine strain of the the virus caused this severe complication. Analysis of this viral DNA demonstrated a mutation in the viral thymidine kinase gene. Plasmids containing this altered gene were unable to produce functional thymidine kinase in an in vitro translation system. The presence of this mutation would explain the clinical resistance to acyclovir. This is the first report of Oka-strain varicella virus causing severe disease after reactivation and of resistance to acyclovir during an infection caused by this virus.
We describe a neonate with bacterial infection of a cephalohematoma by Escherichia hermannii and with meningitis. We review the literature on infected cephalohematomas and E. hermannii and document the first case of invasive disease due to this pathogen.
Chronic pulmonary inflammation and infection are the leading causes of morbidity and mortality in cystic fibrosis (CF). While the effect of mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) on airways remains controversial, some groups have demonstrated increases in Na(+) and Cl(-) in CF airway surface liquid compared to normal airways. We investigated the consequences of NaCl on pro-inflammatory chemokine and cytokine production by macrophages. Stimulation of mouse macrophages with increasing amounts of NaCl induced macrophage inflammatory protein-2 (MIP-2) and tumor necrosis factor-alpha (TNF-alpha) production. Further, co-incubation of macrophages with NaCl in the presence of either lipopolysaccharide (LPS) or TNF-alpha synergistically increased MIP-2 production. Both the NaCl and NaCl plus LPS responses were partially dependent on endogenous production and autocrine signaling by TNF-alpha. To investigate the role of CFTR in MIP-2 production, we compared the responses of wild-type and DeltaF508 CF mouse macrophages to NaCl and LPS. The responses of macrophages from both strains were indistinguishable. In addition, CFTR mRNA was not expressed in macrophages. Taken together, these findings suggest that NaCl stimulates MIP-2 production by macrophages through a mechanism that is partially dependent on TNF-alpha but independent of macrophage CFTR expression.
Mucosal candidiasis is a common complication of HIV infection and HIV-positive women may develop both oropharyngeal and vaginal disease. Colonization with Candida albicans and related species at either site is a common preceding event in asymptomatic women. To examine the molecular epidemiology of colonizing yeast strains in HIV-positive women, concurrent oropharyngeal and vaginal cultures were obtained from 32 women (mean CD4 count 392 cells/mm3, range 0-1319). Positive oropharyngeal cultures were obtained in 18 (56%) and positive vaginal cultures in 10 (31%). Candida species were isolated from both sites simultaneously in nine (28%) women. All strains were evaluated for restriction fragment length polymorphisms (RFLPs) at the ribosomal DNA locus (using a heterologous 8.4-kb NotI probe from H. capsulatum) and with a C. albicans-specific repetitive DNA probe. Isolates were grouped into three classes by the NotI probe and then members of each class were evaluated with the C. albicans-specific probe. Isolates were subsequently evaluated by random amplified polymorphic DNA (RAPD) PCR with four arbitrary primers to detect strain-specific differences. All isolates tested were unique and could be discriminated by RFLP or RAPD PCR. Vaginal and oropharyngeal isolates from the same individual in all nine cases were dissimilar, suggesting that the dominant strain of Candida colonizing different body sites is different. These findings suggest that the epidemiology of Candida infection in HIV disease is complex, that the development of oropharyngeal and vaginal disease may be disassociated, and that HIV-positive patients are each infected by their own unique strains of Candida.
As a follow-up to a 1992 study of respiratory isolation, we studied compliance with recommendations for respiratory isolation through smokestick testing (1993) and surveys (1994). Effective negative pressure was demonstrated in 80 of 156 rooms and was associated with the presence of anterooms (P<.001). The proportion of surveyed hospitals periodically testing isolation rooms increased from 0% (1992) to 30% (1993) to 100% (1994; P<.001).
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