Biomedical subjects

Joshua K Schaffzin

Publications and source records attributed to Joshua K Schaffzin.

3 recordsLinked to original sources

PubMed2006

Multistate outbreak of Fusarium keratitis associated with use of a contact lens solution.

CONTEXT: Fusarium keratitis is a serious corneal infection, most commonly associated with corneal injury. Beginning in March 2006, the Centers for Disease Control and Prevention received multiple reports of Fusarium keratitis among contact lens wearers. OBJECTIVE: To define the specific activities, contact lens hygiene practices, or products associated with this outbreak. DESIGN, SETTING, AND PARTICIPANTS: Epidemiological investigation of Fusarium keratitis occurring in the United States. A confirmed case was defined as keratitis with illness onset after June 1, 2005, with no history of recent ocular trauma and a corneal culture growing Fusarium species. Data were obtained by patient and ophthalmologist interviews for case patients and neighborhood-matched controls by trained personnel. Available Fusarium isolates from patients' clinical and environmental specimens were genotyped by multilocus sequence typing. Environmental sampling for Fusarium was conducted at a contact lens solution manufacturing plant. MAIN OUTCOME MEASURES: Keratitis infection with Fusarium species. RESULTS: As of June 30, 2006, we identified 164 confirmed case patients in 33 states and 1 US territory. Median age was 41 years (range, 12-83 years). Corneal transplantation was required or planned in 55 (34%). One hundred fifty-four (94%) of the confirmed case patients wore soft contact lenses. Forty-five case patients and 78 controls were included in the case-control study. Case patients were significantly more likely than controls to report using a specific contact lens solution, ReNu with MoistureLoc (69% vs 15%; odds ratio, 13.3; 95% confidence interval, 3.1-119.5). The prevalence of reported use of ReNu MultiPlus solution was similar between case patients and controls (18% vs 20%; odds ratio, 0.7; 95% confidence interval, 0.2-2.8). Fusarium was not recovered from the factory, warehouse, solution filtrate, or unopened solution bottles; production of implicated lots was not clustered in time. Among 39 isolates tested, at least 10 different Fusarium species were identified, comprising 19 unique multilocus genotypes. CONCLUSIONS: The findings from this investigation indicate that this outbreak of Fusarium keratitis was associated with use of ReNu with MoistureLoc contact lens solution. Contact lens users should not use ReNu with MoistureLoc.

Adult↗

PubMed2004

Expression of the Pneumocystis carinii major surface glycoprotein epitope is correlated with linkage of the cognate gene to the upstream conserved sequence locus.

The major surface glycoprotein (MSG) is a variable surface antigen of the pathogenic fungus Pneumocystis carinii. Many forms of MSG are encoded by a gene family. Expression of the MSG gene family is believed to be controlled in a cis-dependent fashion. Transcription of a given MSG gene is correlated with linkage of that gene to a unique locus called the upstream conserved sequence (UCS). These data predict that the MSG protein on a given organism will match that encoded by the MSG gene at the UCS locus in that organism. To test this hypothesis, a monoclonal antibody (mAb) that recognizes a small number of MSG isoforms was identified, and the DNA sequence encoding the mAb epitope (epitope-encoding sequence, EES) was determined. Western blotting, immunofluorescence and DNA hybridization showed that expression of the mAb epitope was associated with the presence of the EES at the UCS locus. Correlation of epitope expression and UCS linkage supports the hypothesis that expression of a particular MSG on the surface requires UCS linkage of the gene encoding it.

Amino Acid Sequence↗

PubMed2003

Evaluation of syphilis reactor grids: optimizing impact.

BACKGROUND: A syphilis reactor grid (SRG) is an administrative tool based on the sex, age, and serologic titer of persons with reactive serologic tests for syphilis (reactors) that is used by Sexually Transmitted Disease program staff to prioritize follow-up investigations of persons who may have syphilis. The National Plan to Eliminate Syphilis from the United States recommends that state and local health departments regularly evaluate the effectiveness of their SRGs. However, there are limited methods for SRG evaluation that are feasible for sexually transmitted disease programs. GOAL: To evaluate the sensitivity and predictive value of five currently used SRGs. STUDY DESIGN: Comparative evaluation of five SRGs in four different populations. RESULTS: The percentage of true syphilis cases not assigned to an investigation by an SRG (missed cases) was dependent on syphilis prevalence among reactors and on the SRG. The percentage of reactors assigned to an investigation by an SRG that were not true cases was primarily dependent on syphilis prevalence among reactors, not SRG design. Cases missed by SRGs were predominantly men aged 30 to 50 years and women aged 20 to 40 years who had low or intermediate serologic titers. CONCLUSION: Monitoring the prevalence of syphilis among reactors is critical because in areas with high prevalence, most SRGs miss a substantial number of cases, and in areas with low prevalence, some SRGs can reduce unnecessary investigations.

Adolescent↗