Kiran Beri

Introduction: Corynebacterium spp. are primarily considered normal flora and dismissed when isolated from clinical specimens. In recent years, Corynebacterium striatum has emerged as a multi-drug resistant human pathogen which can cause nosocomial outbreaks. The organism has infrequently been noted to cause respiratory infections. A retrospective study was conducted to identify the clinical and microbiological features of respiratory infection by Corynebacterium striatum. Methodology: C. striatum isolates from clinical and surveillance samples were tested for susceptibility to antimicrobials and typed by Random Amplification of Polymorphic DNA (RAPD). Clinical data was obtained through a retrospective review of records. Results: 15 isolates from clinical and surveillance samples of 11 hospitalised patients were included. The patients suffered from either an exacerbation of COPD (n = 9) or pneumonia (n = 2). The isolates were all multi-drug resistant. RAPD typing found no evidence of an outbreak/ transmission between patients. Conclusions: Corynebacterium spp. must be considered potential pathogens. Suspicious isolates should be identified to the species level since Corynebacterium striatum is often multi-drug resistant.

Pseudomonas spp are important opportunistic and nosocomial pathogens. One such species is Pseudomonas monteilii (P. monteilii). It has been described as an environmental contaminant and potential pathogen. We identified this organism as the causative agent of an exacerbation of bronchiectasis and an environmental contaminant in our hospital on two separate occasions. P. monteilii was the cause of an exacerbation of bronchiectasis in a 30-year-old HIV negative male. Patient presented with cough with sputum production and exertional dyspnea. The isolate was recovered from a sputum sample in significant counts and definitively identified by Matrix-Assisted Laser Desorption/Ionisation- Time of Flight Mass Spectrometry (MALDI-TOF MS). He was treated with piperacillin-tazobactam and recovered clinically and microbiologically. Another two isolates of the organism were contaminants from the hospital environment. The three isolates were susceptible to all tested antibiotics. Typing by Random amplification of polymorphic DNA (RAPD) found no clonal relationship between them. Less common species of Pseudomonas need to be identified accurately. This organism is identified by commonly used phenotypic systems as P. putida which may have contributed to a lower reported prevalence. P. monteilii is a known environmental contaminant and must also be considered as a potential pathogen, particularly in patients with chronic lung disease.