Anuradha De

Prevalence and risk factors of Metallo β-lactamase producing Pseudomonas aeruginosa and Acinetobacter species in burns and surgical wards in a tertiary care hospital.

Introduction: The production of Metallo-β-lactamases (MBLs) is one of the resistance mechanisms of Pseudomonas aeruginosa and Acinetobacter species. There is not much Indian data on the prevalence of MBLs in burns and surgical wards. Materials and Methods: A total of 145 non-duplicate isolates of carbapenem-resistant Pseudomonas aeruginosa and Acinetobacter species, isolated from pus/wound swabs and endotracheal secretions from burns and surgical wards, were tested for MBL production by modified ethylene diamine tetra acetic acid (EDTA) disc synergy and double disc synergy tests. Results: Prevalence of MBLs was 26.9% by both the above tests. All MBL-positive isolates were multidrug resistant. Only 6.06% (2/33) P.aeruginosa and 16.67% (1/06) Acinetobacter species were susceptible to piperacillin-tazobactam and netilmycin, respectively. These patients had multiple risk factors like >8 days hospital stay, catheterization, IV lines, previous antibiotic use, mechanical ventilation, etc. Graft application and surgical intervention were significant risk factors in MBL-positive patients. Overall mortality in MBL-positive patients was 34.21%. Conclusion: Emergence of MBL-producing Pseudomonas aeruginosa and Acinetobacter species in this hospital is alarming, which reflect excessive use of carbapenems and at the same time, pose a therapeutic challenge to clinicians as well as to microbiologists. Therefore, a strict antibiotic policy and implementation of proper infection control practices will go a long way to prevent further spread of MBLs. Detection of MBLs should also become mandatory in all hospitals.

Microbiological assessment of cadaver skin grafts received in a Skin Bank

PURPOSE Study on the microbiological assessment of cadaver skin grafts was undertaken in the Skin Bank at the Department of Surgery in L.T.M. Medical College and Hospital, Mumbai, India. PROCEDURE Microbiology of the skin grafts was studied immediately on receipt and after antibiotic treatment. The antimicrobial and antifungal agents used were crystalline penicillin, gentamicin, amikacin, ceftazidime and amphotericin B. FINDINGS Escherichia coli, Staphylococcus aureus and Candida species were the predominant microorganisms isolated on pre-processing cultures from cadaver skin grafts. Seventy percent of pre-processing cultures showed growth. After first cycle antibiotic treatment, 52.4% of grafts showing growth became sterile. Growth of Klebsiella pneumoniae persisted in two cases, even after 2nd cycle of antibiotic treatment. After the use of antifungal, 57.1% of those showing fungal growth became sterile. CONCLUSION Various antibiotics and antifungals can be used in order to minimize the discard rate of skin grafts.

Mortality audit of neonatal sepsis secondary to Acinetobacter

Background: Multidrug resistant Acinetobacter infection has emerged as an important pathogen in neonatal sepsis in the recent years causing morbidity as well as mortality. Materials and Methods: A retrospective analysis was performed over a one and a half year period of all neonates admitted with sepsis in our neonatal intensive care unit (NICU), who developed Acinetobacter infection and to identify mortality-associated risk factors in these neonates. Results: Incidence of neonatal septicaemia due to Acinetobacter species was 9.18%. All were cases of early onset sepsis. Predominant species isolated was Acinetobacter baumanii (67.5%). The major symptoms were lethargy and poor feeding. The major signs were tachypnoea, rib retraction, and respiratory distress. The major fetal risk factors were low birth weight and prematurity. Overall, 53.75% were multidrug resistant (MDR) Acinetobacter. Resistance to more than two drugs (MDR) was statistically significant in A. baumanii as compared with nonbaumanii. Overall mortality due to Acinetobacter neonatal sepsis was 20%. Septicemia due to A. baumanii was associated with higher mortality than those due to nonbaumanii isolates. Lethargy, tachypnoea, rib retraction, tachycardia, respiratory distress, and mechanical ventilation were significant predictors of mortality. Conclusion: Multidrug resistant Acinetobacter infection is fatal, particularly in premature and low birth weight neonates. Therefore, an effective infection control policy and rational antibiotic use are mandatory in neonatal intensive care areas of each hospital in order to control Acinetobacter infection and improve outcome.

LEPTOSPIROSIS OUTBREAK IN 2005: L.T.M.G. HOSPITAL EXPERIENCE

Nine hundred and forty two serum samples from clinically suspected cases of leptospirosis admitted in Lokmanya Tilak Municipal General Hospital, Mumbai during July-September 2005 were tested by LeptoTek Dri-dot/Leptocheck. One hundred and sixty five positive sera by these tests were sent to I.R.R., Mumbai, for detection of leptospira IgM antibodies by ELISA (PanBio). Eighty seven positive sera were also sent to B.J. Medical College, Pune, for microscopic agglutination test (MAT) for serovar identification. Seropositivity with LeptoTek Dri-dot/Leptocheck was 34.3%. Adults and males predominated. All patients were febrile. The commonest presentation in adults was jaundice (81.4%), followed by oliguria (37.6%). In children, myalgia was commonest (75.6%), followed by conjunctival suffusion (54.7%). IgM ELISA positivity was 69.1% and MAT positivity was 29.9%. Commonest serovar detected in this geographical area was Leptospira icterohaemorrhagiae (42.9%), followed by L. bataviae, L. tarassovi, and L. pomona . Considering at least two of the above three serological tests positive, 127 cases could be diagnosed and only 89.8% of them could be diagnosed by ELISA and rapid test. Therefore, along with rapid serological tests, IgM ELISA should be routinely done for laboratory diagnosis of leptospirosis.

Deceased donor skin allograft banking: Response and utilization

Background: In the absence of xenograft and biosynthetic skin substitutes, deceased donor skin allografts is a feasible option for saving life of patient with extensive burn injury in our country. Aims: The first deceased donor skin allograft bank in India became functional at Lokmanya Tilak Municipal (LTM) medical college and hospital on 24th April 2000. The response of Indian society to this new concept of skin donation after death and the pattern of utilization of banked allografts from 2000 to 2010 has been presented in this study. Settings and Design: This allograft skin bank was established by the department of surgery. The departments of surgery and microbiology share the responsibility of smooth functioning of the bank. Materials and Methods: The response in terms of number of donations and the profile of donors was analyzed from records. Pattern and outcome of allograft utilization was studied from specially designed forms. Results: During these ten years, 262 deceased donor skin allograft donations were received. The response showed significant improvement after counselling was extended to the community. Majority of the donors were above 70 years of age and procurement was done at home for most. Skin allografts from 249 donors were used for 165 patients in ten years. The outcome was encouraging with seven deaths in 151 recipients with burn injuries. Conclusions: Our experience shows that the Indian society is ready to accept the concept of skin donation after death. Use of skin allografts is life saving for large burns. We need to prepare guidelines for the establishment of more skin banks in the country.

Isolation of Vibrio cholerae El Tor Serotype Inaba in 2006 and the most common phage type of V. cholerae in Mumbai

Sir, A total of 168 strains of Vibrio cholerae were isolated and tested over a period of 3 years (2004-2006). The strains were identified by standard methods(1) and were identified using a slide agglutination test with Vibrio cholerae O1 antisera and biotyped using a polymyxin B sensitivity test. The non-agglutinating strains were tested with V. cholerae O-139 antisera. Of 168 strains, 96 were isolated in 2004, 39 were isolated in 2005, and 33 were isolated in 2006. Eighty-three V. cholerae O1 isolates were sent to the National Institute of Cholera and Enteric Diseases (NICED) in Kolkata for serotyping and phagetyping. All the V. cholerae O1 isolates were of El Tor biotype. Among the two non-agglutinating vibrios isolated in 2005, both did not agglutinate with O-139 antisera. V. cholerae El Tor serotype Inaba was found only in 2006. The isolates of 2004 and 2005 were of the Ogawa serotype. In a previous study in the same institute, all isolates detected over a period of 5 years (1996-2000) were of the Ogawa serotype.(2) From 2001 to 2005, all isolates were V. cholerae El Tor Ogawa (unpublished). We had isolated serotype Inaba in 2006 for the first time. A shift in the occurrence of Ogawa and Inaba serotypes in a given area are thought to be a consequence of the genetic reversal that occurs in-vivo and in-vitro and is possibly mediated by the immune pressure in the population.(3) It appears that as an alternate to the Ogawa serotype, Inaba have appeared to aid the persistence of cholera and thus perpetuate the spread of Vibrio cholerae El Tor. All the isolates during 2004 to 2006 were Basu and Mukherjee phage type 2. Turbadkar et al.(4) from Mumbai have reported Ogawa serotypes in 2004 and all belonged to phage type 4. In the new phage typing scheme, out of 26 isolates sent to NICED in 2004, 14 were T26 and 12 were T27. Out of 39 isolates sent in 2005, 33 were T27 and 6 were other phage types (T13, T21, T22, T25, T23, or T15). In 2006, out of 18 isolates sent to NICED, 17 were T27 and only 1 was T26. Therefore, the most common phage type in this part of Mumbai is T27 (74.7%), followed by T26 (18.1%). In the study by Turbadkar et al.,(4) the majority belonged to phage type 27 (97.5%), which is in accordance with the present study. The 168 isolates of V.cholerae showed maximum sensitivity to amikacin (92.3%), followed by cefotaxime (89.9%). Tetracycline sensitivity was 91.1% followed by norfloxacin (86.3%). In the previous study during 1996-2000, tetracycline sensitivity was 39.6% and norfloxacin sensitivity was 46.2%.(2) Therefore, tetracycline and norfloxacin sensitivity have increased over the years. Co-trimoxazole and nalidixic acid susceptibility was only 2.4% and 1.2%, respectively in the present study. A decrease in sensitivity to nalidixic acid was observed in the present study (13.6% in previous study).(2)

Bacterial Etiology of Diarrhea in Children Admitted in Hematologic Unit in aTertiary Care Hospital

Introduction: Diarrhea is a frequent complication observed in patients with hematologic cancer. The normal fecal micro flora changes in chemotherapy-induced diarrhea, which shows a higher proportion of aerobic and oxygentolerant bacteria. Hence the causative bacterial pathogens maybe different than the usual etiology. Objectives: Therefore, the objective of the study was to find outthe etiology of diarrhea in children suffering from hematological malignancy and who are on chemotherapy. Material and Methods: A retrospective study was carried out on patients in hematologic unit of pediatric ward over a period of one and half years at a tertiary care hospital in Mumbai. A total of 55 stool samples from patients of hematological malignancy who presented with diarrhea, were included in this study. The samples were processed as per standard techniques and the bacterial pathogens were identified by standard biochemical tests. Results: Growth of pathogenic bacteria was seen in 15 (27.27%) stool samples, of which 13 patients had acute lymphatic leukemia(ALL) and only two patients had acute myeloid leukemia (AML). Among 15 growths, 11 grew Pseudomonas aeruginosa, two grew Morganella morganii and one each grew Aeromonas hydrophila and Klebsiella pneumoniae. Conclusion: Organisms usually considered as non pathogenic may cause disease in immunocompromised patients. Stool specimens of all leukemic patients suffering from diarrhea and on chemotherapy, should be sent routinely for culture, so as to find out the exact cause of diarrhea.

Campylobacter Jejuni from Perforated Gastric Ulcer: A Rare Case

Campylobacter species induced enteritis is among the most common in the world. However, its association with gastric perforation is not well documented. We report here a case of a 27-year-old male who presented with a gastric perforation. Gastric biopsy sample revealed Gram-negative spiral bacilli and culture on modified Thayer-Martin agar yielded Campylobacter jejuni. The identification was confirmed by standard biochemical tests. This is probably the first documented case report from India of C. jejuni from the gastric biopsy.

Comparison of the Lysis Centrifugation Method with the Conventional Blood Culture Method in Cases of Sepsis in a Tertiary Care Hospital

Introduction: Physicians and microbiologists have long recognized that the presence of living microorganisms in the blood of a patient carries with it considerable morbidity and mortality. Hence, blood cultures have become critically important and frequently performed test in clinical microbiology laboratories for diagnosis of sepsis. Objectives: To compare the conventional blood culture method with the lysis centrifugation method in cases of sepsis. Materials and Methods: Two hundred nonduplicate blood cultures from cases of sepsis were analyzed using two blood culture methods concurrently for recovery of bacteria from patients diagnosed clinically with sepsis – the conventional blood culture method using trypticase soy broth and the lysis centrifugation method using saponin by centrifuging at 3000 g for 30 minutes. Results: Overall bacteria recovered from 200 blood cultures were 17.5%. The conventional blood culture method had a higher yield of organisms, especially Gram positive cocci. The lysis centrifugation method was comparable with the former method with respect to Gram negative bacilli. The sensitivity of lysis centrifugation method in comparison to conventional blood culture method was 49.75% in this study, specificity was 98.21% and diagnostic accuracy was 89.5%. In almost every instance, the time required for detection of the growth was earlier by lysis centrifugation method, which was statistically significant. Contamination by lysis centrifugation was minimal, while that by conventional method was high. Time to growth by the lysis centrifugation method was highly significant (P value 0.000) as compared to time to growth by the conventional blood culture method. Conclusion: For the diagnosis of sepsis, combination of the lysis centrifugation method and the conventional blood culture method with trypticase soy broth or biphasic media is advocable, in order to achieve faster recovery and a better yield of microorganisms.