Infection and colonization by Corynebacterium pseudodiphtheriticum: a 9-year observational study in a university central hospital.

Despite constituting part of the human commensal flora, Corynebacterium pseudodiphtheriticum has been recognized as a potentially infectious agent, most frequently in immunocompromised patients or individuals with other morbidity factors, but significant association to comorbid states remains unproven. This study's purpose was to assess clinical significance, risk factors for infection and antimicrobial susceptibility of C. pseudodiphtheriticum isolates. A retrospective observational study was conducted. Relevance of isolation was determined by clinical, laboratory, and imaging criteria. Forty-nine isolates occurred in 47 episodes. Colonization was assumed in 12% and infection in 78%, of which 51% were nosocomial. Patients with infection were older, with male predominance; both age and gender were statistically significant (p < 0.05) between infection and colonization groups. Although dyslipidemia (58%), arterial hypertension (58%), invasive procedures (56%), and chronic lung disease (50%) were prevalent in the infection group, no comorbidity was a significant risk factor for infection compared with colonization. Charlson comorbidity index showed no statistically difference between groups. Mortality rate was 14% in infection. Respiratory samples were the main isolation product; all tested strains were susceptible to amoxicillin/clavulanate and vancomycin. Resistant strains were observed for clindamycin (77%) and erythromycin (48%). C. pseudodiphtheriticum isolation was associated with infection in most cases. Despite the high prevalence of comorbidities and invasive procedures, no factors other than age and gender were significantly associated with infection. Although C. pseudodiphtheriticum may constitute a contaminant or colonizer in clinical samples, positive cultures in patients with signs and symptoms consistent with infection should not be neglected.

Nontravel-related invasive Entamoeba histolytica infection with probable heterosexual transmission.

INTRODUCTION: In industrialized countries, amebiasis usually occurs in migrants and travelers returning from areas where the disease is endemic, primarily by ingestion of contaminated food or water. Person-to-person transmission can occur, mainly by fecal-oral contact, but sexual transmission has also been described [1,[3], [4], [5]]. PRESENTATION OF CASE: We report a man with Entamoeba histolytica colitis and a large liver abscess (16.5 × 14 cm) in Portugal, who had no relevant travel history and whose only risk factor was his heterosexual partner. The abscess required drainage of 1950 mL of "chocolate-milk" purulent fluid, with rapid symptomatic improvement. The diagnosis was established by real-time reverse transcription PCR for Entamoeba histolytica in the liver aspirate, with positive IgG antibodies. He received a total of 16 days of ceftriaxone and metronidazole followed by 7 days of paromomycin. CONCLUSION: As enteric infections may be sexually transmitted, in industrialized countries, even in the absence of travel, sexual history should not be neglected.