The challenging diagnosis of overlapping oral primary/secondary syphilis with nonreactive serology.

The prevalence of oral syphilis, known as "the great imitator" because of its diagnostic complexity and varied clinical manifestations, is increasing worldwide, particularly in people living with HIV (PLWH), who could present false-negative serological results. Although some studies have described the variable presentation of oral syphilis in the context of HIV infection, the difficulty in distinguishing between the primary and secondary stages, clinically and histopathologically, underscores the need to describe atypical cases. We report the case of a 28-year-old HIV-positive man presenting with a 3-month history of painless white/red ulcerated lesion on the soft palate.

CLINICAL AND EPIDEMIOLOGICAL CHARACTERISTICS OF PATIENTS DIAGNOSED WITH COVID-19 IN A TERTIARY CARE CENTER IN MEXICO CITY: A PROSPECTIVE COHORT STUDY.

Background: Regional information regarding the characteristics of patients with coronavirus disease (COVID)-19 is needed for a better understanding of the pandemic.

Objective: The objective of the study to describe the clinical features of COVID-19 patients diagnosed in a tertiary-care center in Mexico City and to assess differences according to the treatment setting (ambulatory vs. hospital) and to the need of intensive care (IC).

[Patients with solid organ transplantation and skin cancer: determination of risk factors with emphasis in photoexposure and immunosuppressive regimen. Experience in a third level hospital].

Background: Non-melanoma skin cancer (NMSC) is the most common malignancy in transplant patients. The incidence of basal cell carcinoma (BCC) is 10 times greater than in the general population, while squamous cell carcinoma (SCC) is 100 times greater. The relationship between the BCC and SCC reverses and increases according to the degree of immunosuppression and sun exposure.

[Flouroquinolone activity in clinical isolates of Streptococcus pneumoniae with different susceptibility to penicilline: an epidemiological study in five cities of Mexico].

Objective: Determine the susceptibility to five fluoroquinolones and cross-resistance of pneumococcusclinical isolates with different penicillin susceptibilities gathered in a community-based study.

Design: Cross-sectional survey.

Materials: Two hundred and thirty one (231) isolates were obtained from respiratory secretions or blood specimens from 231 patients with acquired acute respiratory infection or bacteremia.

High prevalence of Chlamydia pneumoniae seropositivity in Mexican patients with ischemic heart disease.

Background: Risk factors for development of atherosclerosis, such as hyperlipidemia, high blood pressure, smoking habit, and diabetes mellitus, have been identified. The possibility that infectious agents may unchain biological and biochemical reactions related to inflammation, atherogenesis, and vascular thromboses events have recently been described. Chlamydia pneumoniae has been associated with coronary artery disease in some seroepidemiology studies.

Prevalence and risk factors associated with the presence of peripheral neuropathy in patients with hepatitis C virus infection.

Objectives: To determine the frequency and risk factors associated with peripheral neuropathy in a population of patients with hepatitis C virus infection.

Methods: Cross-sectional study. Electrophysiological assessment included bilateral motor and sensory conduction studies of four limbs.