Noyal Mariya Joseph

Ventilator-associated pneumonia: A review

Ventilator-associated pneumonia (VAP) is the most frequent intensive-care-unit (ICU)-acquired infection, with an incidence ranging from 6 to 52% [1,2,3,4]. Several studies have shown that critically ill patients are at high risk for getting such nosocomial infections [3,4]. VAP continues to be a major cause of morbidity, mortality and increased financial burden in ICUs [5,6,7,8]. Over the years there has been a significant advance in our understanding of ventilator associated pneumonia. This article reviews the various aspects of VAP such as definition, risk factors, etiological agents, diagnosis, treatment and prevention with emphasis on the recent advances.

Ventilator-associated pneumonia: role of colonizers and value of routine endotracheal aspirate cultures

OBJECTIVES To determine the role of colonizers in the causation of ventilator-associated pneumonia (VAP) and the value of routine pre-VAP endotracheal aspirate (EA) cultures in appropriately treating VAP. METHODS A prospective observational cohort study was conducted over a period of 15 months. Two hundred patients on mechanical ventilation for>48h were studied. RESULTS Acinetobacter spp (33.7%) and Pseudomonas spp (29.8%) were the most common colonizers. Of the 200 patients, 36 developed VAP. In 20 VAP patients, the pre-VAP EA culture-based strategy was not useful. However, in the remaining 16 VAP patients, a pre-VAP EA culture-based strategy would have appropriately treated 13 (81%; 95% confidence interval (CI) 62-100%), in comparison to only nine (56%; 95% CI 32-80%) by the American Thoracic Society (ATS) strategy. The seven patients in whom the ATS guidelines were inappropriate had Acinetobacter spp and Pseudomonas spp resistant to the higher antibiotics recommended by the ATS for multidrug-resistant pathogens. The positive predictive values of Pseudomonas aeruginosa, Acinetobacter baumannii, and methicillin-resistant Staphylococcus aureus (MRSA) isolated from pre-VAP EA cultures were 88%, 83%, and 100%, respectively. CONCLUSION VAP patients should be treated based on ATS guidelines, but whenever P. aeruginosa, A. baumannii, and MRSA are isolated from pre-VAP EA cultures, the initial antibiotic therapy should be extended to treat these.

Changing Trends in Resistance Pattern of Methicillin Resistant Staphylococcus aureus

BACKGROUND Methicillin resistance in Staphylococcus aureus is associated with multidrug resistance, an aggressive course, increased mortality and morbidity in both community and health care facilities. Monitoring of newly emerging and prevalent Methicillin Resistant Staphylococcus aureus (MRSA) strains for their resistance patterns to conventional as well as novel drugs, are essential for infection control. AIMS To study the changing trends in resistance patterns of MRSA at our hospital. SETTINGS AND DESIGN This cross sectional study was carried out in a 750 bed tertiary care hospital in south India. MATERIAL AND METHODS One hundred and two clinical isolates of MRSA which were obtained in 2004-2011 were identified by using oxacillin, cefoxitin disc diffusion test and oxacillin screening agar test. Antibiotic susceptibility test was done for commonly used non beta lactam anti-Staphylococcal drugs, as well as for anti-MRSA drugs like vancomycin, linezolid, mupirocin and rifampicin. Minimum inhibitory concentration (MIC) of vancomycin was determined by using Vancomycin HiComb strip (Himedia, Mumbai, India). Statistical Analysis which was done: Chi-square test and proportions were used to compare the two groups. RESULTS MRSA isolates showed high resistance to co-trimoxazole (82.3%), ciprofloxacin (76.4%), gentamicin (64.7%) and tetracycline (49%) as compared to other drugs. High prevalence of ciprofloxacin resistance was detected, particularly among outpatients. Multi resistant MRSA with a ≥ 3 non-beta lactam agent resistance was 79%. All MRSA isolates were sensitive to vancomycin, linezolid, mupirocin and rifampicin. MRSA had displayed increase in resistance to most antibiotics except tetracycline in recent years. CONCLUSIONS Taking into consideration the prevalence of multidrug resistance in MRSA, resistance patterns should be evaluated periodically and antibiotic therapy should be guided by susceptibility testing.

Relationship between Antimicrobial Consumption and the Incidence of Antimicrobial Resistance in Escherichia coli and Klebsiella pneumoniae Isolates

INTRODUCTION Gram negative organisms are one of the major causes of nosocomial diseases. Development of resistance to antibiotics by these organisms increases their risk in clinical treatment of patients. It also affects morbidity and mortality hence needs to be monitored and controlled. AIM The aim of the present study was to analyse the correlation between consumption of parenteral antibiotics and the rates of antimicrobial resistance among the Escherichia coli and Klebsiella pneumoniae isolates collected during Dec 2010 - Jun 2013 from JIPMER hospital. MATERIALS AND METHODS Consumption data of parenteral antibiotics in J01 category of Anatomical Therapeutic Chemical (ATC) in JIPMER was obtained and expressed in Defined Daily Doses (DDD) per 1000 inhabitants. Valid consumption and resistance data during the period Dec 2010 to Jun 2013 were obtained at 6 month intervals and were correlated to draw a relationship between antimicrobial consumption and its impact on drug resistance for Escherichia coli and Klebsiella pneumoniae. RESULTS Escherichia coli isolates showed high resistance for increased use of gentamycin and ciprofloxacin. Increase in antibiotic consumption increases the resistance for Escherichia coli except for amikacin. Among the Klebsiella isolates, meropenem and gentamycin showed high correlations followed by ceftazidime, amikacin, ceftriaxone and ciprofloxacin. CONCLUSION In summary, a statistically significant association was noticed between consumption of the studied antimicrobials and resistance of Escherichia coli isolates, except for amikacin and ceftazidime. In the case of Klebsiella pneumoniae, there was a statistically significant association between the resistance rates and consumption of gentamycin, ceftazidime and meropenem. Further, a linear relationship was noted between antimicrobial consumption and resistant isolates of Escherichia coli and Klebsiella pneumoniae, except for Escherichia coli resistance to amikacin.

Subcutaneous zygomycosis caused by Mucor hiemalis in an immunocompetent patient

Zygomycosis is an opportunistic fungal infection with a high mortality rate. It is known to cause invasive disease in immunocompromised hosts but it may produce only cutaneous/ subcutaneous infections in immunocompetent hosts. Treatment is difficult due to its fulminant course and lack of effective anti-fungal drugs. Here, we report a rare case of subcutaneous zygomycosis caused by Mucor hiemalis in an immunocompetent patient without any debilitating illness. The patient was successfully treated by aggressive surgical debridement and anti-fungal therapy.

Performance of chromogenic media for Candida in rapid presumptive identification of Candida species from clinical materials.

Background: In perspective of the worldwide increase in a number of immunocompromised patients, the need for identification of Candida species has become a major concern. The development of chromogenic differential media, introduced recently, facilitate rapid speciation. However, it can be employed for routine mycology workup only after an exhaustive evaluation of its benefit and cost effectiveness. This study was undertaken to evaluate the benefit and cost effectiveness of chromogenic media for speciation of Candida clinical isolates. Materials and Methods: Sputum samples of 382 patients were screened for the presence of Candida spp. by Gram stain and culture on sabouraud dextrose agar. Candida species were identified using Gram stain morphology, germ tube formation, cornmeal agar with Tween-80, sugar fermentation tests and morphology on HiCrome Candida differential agar. All the Candida isolates were inoculated on HiCrome Candida agar (HiMedia, Mumbai, India). Results: The sensitivity and specificity of HiCrome agar for identification of Candida albicans were 90% and 96.42%, respectively whereas sensitivity and specificity of carbohydrate fermentation test were 86.67% and 74.07%, respectively. Sensitivity and specificity values of HiCrome agar for detection of C. albicans, Candida parapsilosis and Candida glabrata were above 90%. Conclusions: We found HiCrome agar has high sensitivity and specificity comparable to that of the conventional method. In addition, use of this differential media could significantly cut down the turnaround time as well as cost of sample processing.

Role of clinical diagnosis of ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is an important nosocomial infection associatedwith increasedmorbidity andmortality. VAP is defined as pneumonia that occurs more than 48 hours after initiation of mechanical ventilation.1 It is difficult to diagnose VAP accurately, and a high indexof suspicion is required. VAP is clinically suspected usually based on the presence of fever (temperature >38.3 C), blood leukocytosis (>10,000/mm3), or leukopenia (<4,000/mm3), purulent tracheal secretions, and a new and/or persistent radiographic infiltrate. Pugin et al proposed the clinical pulmonary infection score (CPIS), based on 6 clinical parameters (0-2 points each), such as fever, leukocyte count, quantity and purulence of tracheal secretions, oxygenation, type of radiographic abnormality, and results of sputum culture and Gram’s stain.2 We performed a prospective study over a period of 15 months to determine the value of various clinical parameters indiagnosingVAP. VAP was diagnosed in patients with a quantitative endotracheal aspirate culture showing 105 colony-forming units/mL after 48 hours of mechanical ventilation. A total of 200 patients was prospectively evaluated, of whom 36 (18%) developed VAP during their intensive care unit stay. The mean CPIS of VAP group (8.9 .8262) was significantly higher than that of non-VAP group (2.5 2.022) (P < .0001). There was a significant and very strong positive correlationbetweenCPIS>6andVAP (Pearsoncorrelation,0.909;P< .0001). The CPIS >6 had 100% sensitivity, 96.3% specificity, 85.7% positive predictive value, and 100% negative predictive value in diagnosing VAP. Similarly, Niederman had shown that a clinical definition of VAP based on CPIS >6 was associated with a high likelihoodofpneumoniawithasensitivityof93%andaspecificityof100% when compared with quantitative bronchoalveolar lavage culture.3 Therefore, CPIS >6 may be considered diagnostic of VAP. In the critically ill patients on mechanical ventilation, the clinical symptoms and signs of pneumonia may vary. In our study, logistic regression analysis showed that temperature 38.5 C (P 1⁄4 .008), oxygenation (PaO2/FiO2 mm Hg 240; P < .0001), and abnormal chest x-ray (P1⁄4 .029)were independentpredictors ofVAP. Therefore, presenceof these parameters should raise the suspicion of VAP in patients on mechanical ventilation for >48 hours. The presence of asymmetric pulmonary infiltrates on chest radiograph consistent with VAP may sometimes be caused by various noninfectious conditions. However, certain chest radiograph findings, such as progressive rapid cavitation of the pulmonary infiltrate, an air space process abutting a fissure, and a single air bronchogram, are associated with 96% specificity for diagnosing VAP and therefore can be reliably used.1

Persistent earache due to tonsillolith.

Tonsilloliths are rare dystrophic calcification formed as a result of chronic inflammation of the tonsils. Tonsilloliths tend to occur more commonly with increasing age and are relatively rare in children. We report a case of unilateral tonsilloliths in an eight-year-old boy, who presented with earaches and history of regurgitating tiny yellowish-white foul smelling pellets. The tonsilloliths were successfully removed under local anaesthesia following which the symptoms subsided.

Role of Appropriate Therapy in Combating Mortality among the Ventilated Patients.

CONTEXT Ventilator associated pneumonia (VAP) is a nosocomial infection prevalent among the intensive care unit (ICU) patients despite proper infection control practices. The diagnosis of VAP still remains controversial and hence the mortality rate is higher among this group of patients. AIM The aim of our study was to identify the antibiotic pattern and the appropriateness of treatment followed in the ICU in relation with the clinical pulmonary infection score (CPIS) as a tool to diagnose VAP. This was compared with patients who had an inappropriate treatment in comparison to the CPIS and the clinical outcome. RESULTS Out of the 18 VAP patients, 12 (66.7%) received appropriate therapy based on the antibiotic susceptibility pattern of the causative organism, while 1 (5.5%) received partially inappropriate therapy and 5 (27.8%) received totally inappropriate therapy. Nine of the 18 (50%) VAP patients died, while only 5 of the 58 (8.6%) patients without VAP died. 72.2% patients with VAP received appropriate treatment based on the sensitivity of the isolates. The mortality rate in VAP patients receiving inappropriate therapy was 80%, while in those receiving appropriate therapy the mortality rate was 38.5%. The mortality rate among VAP patients with blood culture positivity was 100%, while it was 43.75% among those with negative blood culture. CONCLUSION The mortality rate among the patients receiving inappropriate therapy is high compared to other group of patients. Hence, a proper evaluation and administration of appropriate antibiotics can curb mortality among the ventilated patients.

Neurobehavior of term neonates with neonatal hyperbilirubinemia.

Objective: To find the effect of neonatal hyperbilirubinemia on neurobehavior of term infants. Materials and Methods: This study was undertaken in the neonatal unit of our tertiary care hospital. Term neonates who developed jaundice with serum bilirubin value of above 15 mg/dl within 1st week of life were enrolled in the study. Peak total serum bilirubin (PSB) levels of cases were recorded. Age and sex matched normal controls were assigned to every case. Both the groups were assessed by Brazelton′s neurobehavioral assessment scale (NBAS) and the scores of the individual clusters were compared. Results: Habituation, range of state, autonomic regulation and regulation of state clusters were significantly altered in the case group, while motor organization cluster was mainly affected in neonates with severe jaundice (PSB > 25 mg/dl). No differences were noted in the reflex and orientation NBAS clusters. Conclusion: Neonatal hyperbilirubinemia causes definite alteration in the neonatal neurobehavior.