Molecular identification of Pseudomonas aeruginosa recovered from cystic fibrosis patients.

OBJECTIVE: Precise identification of various morphotypes of Pseduomonas aeruginosa which developed during cystic fibrosis (CF) is of prime importance. We aimed to identify the isolates of P. aeruginosa recovered from CF patients at the genus and species level through primers targeting oprI and oprL genes via PCR. METHODS: Sputum samples or throat swabs were taken from 100 CF patients and plated on cetrimide agar. All suspected colonies were primarily screened for P. aeruginosa by a combination of phenotypic tests. Molecular identification of colonies was performed using specific primers for oprI and oprL genes. RESULTS: Based on phenotypic tests, P. aeruginosa isolates were recovered from 40% of CF patients. Forty isolates yielded amplicon of oprI gene using genus-specific primers confirming the identity of fluorescent pseudomonads. However, 37 of 40 isolates yielded amplicon of oprL gene using species-specific primers, verifying the identity of P. aeruginosa. CONCLUSION: This study showed that the species-specific PCR targeting oprL gene can be used as accurate test for identification of highly adaptable P. aeruginosa in CF patients. This procedure may provide a simple and reliable method for identification of various morphotypes.

Identification and molecular epidemiology of nosocomial outbreaks due to Burkholderia cepacia in cystic fibrosis patients of Masih Daneshvary Hospital, Iran.

INTRODUCTION: B. cepacia complex have emerged as an important opportunistic pathogen in hospitalized and immunocompromised patients. Small hospital outbreaks are frequent and are usually due to a single contaminated environmental source. In this study we were going to investigate the role of B.cepacia complex in those patients suspected to involve with cystic fibrosis and evaluate responsible types in Masih Daneshvary Hospital. METHODS: One hundred specimens were collected from all admitted patients who were suspected to cystic fibrosis to Masih Daneshvary hospital during one year April 2011 till end of March 2012. All were culture and identified standard procedure. All samples were checked by API system (API20NE) and by specific PCR method for genus Bulkhorderia and Bcc as well. Identified strains were finally tested by PFGE system to identifying specific involving pulse-types. RESULT: . Isolation and identification methods revealed 5 specimens were B.cepasia, The frequency of the cystic fibrosis detected at this study was lower than other similar study previously reported. All these isolates showed similar pattern by PFGE standard protocol that may have spread from a single source and could not be attributed to cross infections from patient to patients. DISCUSSION: Application of PFGE and identification of pulse-type is a potential tool to enhance the investigation of apparent nosocomial outbreaks of B.cepacia. However it needs to be adjusted with environmental findings. Implementation of educational programs and adherence to infection control policies are obviously the main element for complete elimination of an outbreak.

Repair of ventral hernias in morbidly obese patients undergoing laparoscopic gastric bypass should not be deferred.

BACKGROUND: There is no consensus regarding the optimal treatment of ventral hernias in patients who present for weight loss surgery. METHODS: Medical records of consecutive morbidly obese patients who underwent laparoscopic Roux-en-Y (LRYGB) gastric bypass with a secondary diagnosis of ventral hernia were reviewed. Only patients who were beyond 6 months of follow-up were included. RESULTS: The study population was 85 patients. There were three groups of patients according to the method of repair: primary repair (59), small intestine submucosa (SIS) (12), and deferred treatment (14). Average follow-up was 26 months. There was a 22% recurrence in the primary repair group. There were no recurrences in the SIS group. Five of the patients in the deferred treatment group (37.5%) presented with small bowel obstruction due to incarceration. CONCLUSION: Biomaterial mesh (SIS) repair of ventral hernias concomitant with LRYGB resulted in the most favorable outcome albeit having short follow-up. Concomitant primary repair is associated with a high rate of recurrence. All incarcerated ventral hernias should be repaired concomitant with LRYGB, as deferment may result in small bowel obstruction.

Aztreonam-induced myelosuppression during treatment of Pseudomonas aeruginosa pneumonia.

Aztreonam is a synthetic, monobactam antibiotic structurally related to the beta-lactam class of drugs. It has inhibitory activity against many aerobic gram-negative bacteria, although it does not inhibit gram-positive or anaerobic bacteria. Administration of aztreonam occasionally is associated with minimal and transient adverse effects. This case report describes a patient we believe experienced bone marrow suppression approximately ten days after aztreonam was given for treatment of pneumonia caused by Pseudomonas aeruginosa. This untoward effect primarily was manifested as neutropenia, although normochromic, normocytic anemia and thrombocytopenia were noted as well. One week after aztreonam was discontinued, the patient's bone marrow suppression resolved spontaneously. Although the mechanism responsible for myelosuppression is unclear, aztreonam may be implicated as the offending agent based on the temporal relationship between the development of neutropenia and its administration, and the resolution of neutropenia upon its discontinuation.