INCIDENCE OF CARBAPENEM RESISTANT NONFERMENTING GRAM NEGATIVE BACILLI FROM PATIENTS WITH RESPIRATORY INFECTIONS IN THE INTENSIVE CARE UNITS

Microbiota of Bronchoalveolar Lavage Samples from Patients of Lower Respiratory Tract Infection – A Changing Trend

Bronchoalveolar lavage (BAL) is the saline wash of the bronchial tree, which aids in diagnosing various pulmonary pathologies. The present study was contemplated with an aim to know the clinical, microbiological profile of BAL samples along with its sensitivity pattern and to assess its utility as a diagnostic tool. This was a prospective observational study, carried over 90 patients presenting with lower respiratory tract infections. The total microbial recovery rate from BAL was 39 (43.3%). The sensitivity, specificity and positive predictive value of BAL were found to be 76.4%, 89.7% and 90.6% respectively. Maximum isolates were bacteria (25.5%) followed by Mycobacterium tuberculosis (MTB) (16.6%) and fungi (1.1%). Predominant bacterial isolates were Gram-negative (81.5%) compared to Gram-positive (18.5%). Multidrug resistance (MDR) in bacteria was seen in 59.2% of isolates. BAL is a valuable diagnostic tool to find not only bacterial but mycobacterial and fungal infections in patients with lower respiratory tract infection (LRTI). A trend towards LRTI with Gram-negative infections is on the rise and they tend to be multidrug-resistant. Hence checking susceptibility patterns is crucial to start evidence-based treatment.

Antibiotic sensitivity pattern of gram negative bacilli isolated from the lower respiratory tract of ventilated patients in the Intensive care unit

Background:

Lower respiratory tract infections (LRTIs) are the most frequent infections among patients in Intensive care units (ICUs).

Aims:

To know the bacterial profile and determine the antibiotic susceptibility pattern of the lower respiratory tract isolates from patients admitted to the ICU.

Settings and Design:

Tertiary care hospital, retrospective study.

Materials and Methods:

Transtracheal or bronchial aspirates from 207 patients admitted to the ICU were cultured, identified, and antibiotic sensitivity was performed by standard methods.

Statistical Analysis Used:

SPSS software was used for calculation of % R of 95% confidence interval (CI).

Results:

Of 207 specimens, 144 (69.5%) were culture positive and 63 (30.4%) showed no growth. From 144 culture positives, 161 isolates were recovered, of which 154 (95.6%) were Gram negative bacilli (GNB). In 17 (11.0%) patients, two isolates per specimen were recovered. The most common GNB in order of frequency were Pseudomonas aeruginosa (35%), Acinetobacter baumannii (23.6%), and Klebsiella pneumoniae (13.6%). A very high rate of resistance (80-100%) was observed among predominant GNB to ciprofloxacin, ceftazidime, co-trimoxazole, and amoxycillin/clavulanic acid combination. Least resistance was noted to meropenem and doxycycline.

Conclusion:

Nonfermenters are the most common etiological agents of LRTIs in ICU. There is an alarmingly high rate of resistance to cephalosporin and β-lactam-β-lactamase inhibitor group of drugs. Meropenem was found to be the most sensitive drug against all GNB. Acinetobacter and Klebsiella spp. showed good sensitivity to doxycycline.

Correlations between genotyping and antibiograms of clinical isolates of Pseudomonas aeruginosa from three different south Indian hospitals

PURPOSE

To compare the molecular relationships and antibiograms of nosocomial isolates of Pseudomonas aeruginosa obtained from three different genres of hospitals located in Southern India, two located at Hyderabad (one private hospital and an ophthalmic hospital) and one in Puducherry (tertiary care teaching hospital). Each of these hospitals, which follow different infection control strategies and various problems associated with it, were investigated.

MATERIALS AND METHODS

Antibiograms generated by disk diffusion susceptibility testing for clinically relevant antibiotics and genotyping through fluorescent amplified fragment length polymorphism analysis (fAFLP) were the tools used in the study.

RESULTS

Molecular genotyping revealed a heterogeneous group of unrelated molecular clusters of P. aeruginosa strains having higher resistance that are apparently being endemic throughout the tertiary care teaching hospital. In eye care hospital, only a few distinct strains of P. aeruginosa predominating the study period were shown to be responsible for outbreaks. The third private hospital witnessed a group of resistant and persistent strains that might have clonally originated from a diverse collection of strains.

CONCLUSIONS

The divergent kind of strains in our study suggests that there may be a direct link between the infection control practices followed in each hospital and kind of strains isolated in that particular setup. The study also emphasizes the need for maintaining infection control practices in hospitals with superior standards, failure of which might result in thriving of persistent P. aeruginosa clones in the hospitals.