S Sujatha

Glycopeptide Resistance in Gram-Positive Cocci: A Review

Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens in the past two decades all over the world and have seriously limited the choices available to clinicians for treating infections caused by these agents. Methicillin-resistant Staphylococcus aureus, perhaps the most notorious among the nosocomial pathogens, was till recently susceptible to vancomycin and the other glycopeptides. Emergence of vancomycin nonsusceptible strains of S. aureus has led to a worrisome scenario where the options available for treating serious infections due to these organisms are very limited and not well evaluated. Vancomycin resistance in clinically significant isolates of coagulase-negative staphylococci is also on the rise in many setups. This paper aims to highlight the genetic basis of vancomycin resistance in Enterococcus species and S. aureus. It also focuses on important considerations in detection of vancomycin resistance in these gram-positive bacteria. The problem of glycopeptide resistance in clinical isolates of coagulase-negative staphylococci and the phenomenon of vancomycin tolerance seen in some strains of Streptococcus pneumoniae has also been discussed. Finally, therapeutic options available and being developed against these pathogens have also found a mention.

Arcanobacterium haemolyticum associated with pyothorax: case report

Arcanobacterium haemolyticum has an established role in the etiology of human pharyngitis. There are increasing reports of systemic infections caused by this organism. From India, we report the first case of Arcanobacterium haemolyticum causing pyothorax in an immunocompetent adolescent male patient. The probable mode of infection is also discussed. The role of A. hemolyticum as an animal pathogen needs further study.

Nosocomial cutaneous zygomycosis in a patient with diabetic ketoacidosis

Zygomycosis is an opportunistic fungal infection with a fulminant course. Varying clinical forms have been described, including cutaneous zygomycosis, which is mainly observed in diabetic and burns patients. We report herein a case of cutaneous zygomycosis of the nose in a 26-year-old female patient with diabetic ketoacidosis, developing secondary to the application of non-elasticized adhesive tape probably contaminated with fungal spores.

SERUM LEVELS OF COPPER AND IRON IN DENGUE FEVER

SUMMARY The role of trace elements in dengue virulence is not yet known. The present study assessed the serum levels of two micronutrients, copper and iron, in cases of dengue fever. The study involved 96 patients of whom 48 had either severe or non-severe forms of dengue (with and without warning signs), and the remaining 48 were patients with other febrile illnesses (OFI), used as controls. Serum levels of copper and iron were evaluated at admission and by the time of defervescence using commercially available kits. At admission, no difference in the level of serum copper was observed between cases and controls. In the group of dengue cases, the copper level was found to be significantly decreased in severe and non-severe cases with warning signs, compared to non-severe cases without warning signs. In contrast, by the time of defervescence the copper level was found to be increased in all dengue cases compared to OFI controls, but no difference was observed among dengue cases. Unlike OFI controls, dengue cases showed an increasing pattern of copper levels from admission until defervescence. On the other hand, no such significant differences were observed in the serum level of iron in the clinical groups, except for a decreased iron level found in severe cases, compared to non-severe dengue without warning signs. The results show that copper is associated with dengue severity and this finding emphasizes the need to investigate the involvement of trace elements in disease severity so as to improve the prognosis of dengue.

Burkholderia pseudomallei infection in a patient with diabetes presenting with multiple splenic abscesses and abscess in the foot: a case report

IntroductionMelioidosis or infection with Burkholderia pseudomallei presents with protean manifestations. We present a case of melioidosis in a diabetic patient from India. The case is presented to highlight the importance of early microbiologic diagnosis and subsequent institution of appropriate therapy to achieve a better prognosisCase presentationA male bachelor around 50 years of age from India presented with low grade fever, bilateral ankle swelling and hypochondrial pain. On examination patient had diabetes and had multiple abscesses in bilateral ankle, knee and splenic region. Microbiologic diagnosis revealed the etiologic agent to be Burkholderia pseudomallei. Patient was managed with iv ceftazidime and surgical excision.ConclusionThe case report highlights the importance of early identification of etiologic agent. B. pseudomallei identification requires a great deal of clinical suspicion as well as alertness on the part of the medical microbiologist as these isolates are often reported as Pseudomonas spp. Correct identification of the etiologic agent is essential as B pseudomallei requires prolonged antimicrobial therapy for a better clinical outcome.

Fatal meningitis caused by vancomycin-resistant enterococci: Report of two cases from south India

Vancomycin-resistant enterococci rarely cause meningitis and present a therapeutic challenge. Antimicrobial susceptibility testing was done for strains of Enterococcus species isolated from CSF samples of patients with meningitis by phenotypic methods. Multiplex polymerase chain reaction was performed to determine the genetic basis of vancomycin resistance of such isolates. We report here two cases of enterococcal meningitis caused by vancomycin-resistant Enterococcus species. One of the isolates was identified as Enterococcus faecalis and the other as Enterococcus gallinarum. We also report the simultaneous presence of vanC1 and vanA resistance genes in the strain of E. gallinarum. To the best of our knowledge, this is the first report of vanA resistance gene in an isolate of E. gallinarum from the Indian subcontinent. This is also the first Indian report of vancomycin-resistant Enterococcus causing meningitis.

Worrisome trends in rising minimum inhibitory concentration values of antibiotics against methicillin resistant Staphylococcus aureus – Insights from a tertiary care center, South India

INTRODUCTION Appearance of isolated reports of resistance to anti-methicillin-resistant Staphylococcus aureus (MRSA) drugs is worrisome underscoring the need to continuously monitor the susceptibility of clinical MRSA isolates to these drugs. Hence, the present study is conducted to determine the susceptibility of MRSA isolates to various classes of anti-MRSA drugs such as vancomycin (glycopeptide), daptomycin (lipopeptide), tigecycline (glycylcycline), and linezolid (oxazolidinone) to determine the MIC50 and MIC90 values, and to observe MIC creep over a three year period, if any, with respect to these drugs. METHODS A total of 200 isolates of MRSA obtained from clinical specimens were included. MIC was determined by E-test for anti-MRSA antibiotics vancomycin, linezolid, daptomycin, and tigecycline. Non-parametric methods (Kruskal-Wallis and Chi-square test) were used to assess MIC trends over time. In addition, MIC50 and MIC90 values were also calculated. RESULTS No isolate was found resistant to vancomycin, daptomycin, or linezolid; five isolates were resistant to tigecycline. Seven VISA isolates were encountered with the MIC value for vancomycin of 4μg/mL. MIC values for vancomycin, tigecycline, linezolid showed a definite increase over a 3-year period which was statistically significant with p-values <0.0001, 0.0032, 0.0242, respectively. When the percentage of isolates with a median MIC value less than or equal to that of the index year was calculated, the change was most striking with vancomycin. The proportion of isolates with higher MIC values was greater in 2014 than 2012 and 2013. CONCLUSION MIC creep was notably observed with vancomycin, and to some extent with tigecycline and linezolid. Selection pressure may result in creeping MICs, which may herald the emergence of resistant organisms.

Fulminant necrotizing fasciitis caused by zygomycetes

To the Editor, Necrotizing fasciitis (NF) is a progressive, rapidly spreading, inflammatory infection located in the deep fascia, with secondary necrosis of the subcutaneous tissues. Most cases are bacterial in origin, caused by mixed aerobic and anaerobic organisms (70%), anaerobes (20%) and aerobes (10%). It is commonly associated with severe systemic toxicity and high mortality in the range of 25–70%. Opportunistic fungal infections are an important cause of cutaneous necrotizing infections in immunocompromised patients, and zygomycosis in the debilitated patient is the most acute and fulminant fungal infection known. Percutaneous risks for developing infection with these fungi are well described, and here in, we present a case of fulminant NF caused by zygomycetes following an intramuscular injection. A 23-year-old female presented in casualty with high-grade fever and a deep ulcer involving the right gluteal region, extending to her thigh and lower back. She gave a history of an unknown intramuscular injection 1 month back. Two weeks later, she had developed a painful ulcer at the site of the injection. She had received some local treatment (details unknown) from a private medical practitioner, but as the lesion started extending, she was referred to our hospital. On examination, patient was febrile, toxic and had a large soft tissue infection spreading along the fascial planes producing necrosis of overlying skin. The area involved included the right gluteal region, thigh and lower back. (Fig. 1A) A clinical diagnosis of NF was established, and an emergency surgical debridement was carried out, and broad-spectrum antibiotics active against both aerobic and anaerobic bacteria ware started. Laboratory studies revealed hemoglobin of 3 gm/ dl, total white cell count of 15,000/mm with raised neutrophils. Serum biochemistry showed deranged renal function test with urea and creatinine 80 and 3 mg/dl, respectively, urine analysis showed proteinuria. Bacterial culture of excised tissue showed growth of Proteus mirabilis, susceptible to third generation cephalosporins and aminoglycosides. In spite of aggressive management, the patient continued to deteriorate. The diagnosis was reviewed, and considering a possibility of cutaneous mycosis, surgically excised tissues were sent for mycological evaluation. KOH wet mount showed broad, nonseptate hyphae (Fig. 1B), and in sections of resected tissue stained by hematoxylin and eosin (Fig. 1C), periodic acid-Schiff (Fig. 1D) and Grocott methenamine silver stains broad hyphae of varying diameters with minimal septation and irregular branching were seen. Fungal culture on Sabouraud’s dextrose agar showed no growth. Amphotericin-B could not be started because patient was in renal failure, and the clinical condition of patient kept on deteriorating despite surgical debridement and intensive medical management. The patient and her family denied further treatment and took leave against medical advice. Zygomycetes class of fungi includes three orders that are Mucorales, Mortierellales and Entomophthorales. The majority of human illness is caused by the Mucorales. Zygomycosis is an emerging cause of NF, and in a recent study, zygomycosis was responsible for 31.03% cases of NF. Early diagnosis is the corner stone of successful treatment of zygomycosis. Treatment of zygomycosis requires several simultaneous approaches: surgical intervention, antifungal therapy and correction of the underlying predisposing condition. Surgical debridement of grossly necrotic tissue is always required; in addition, antifungal agents such as Amphotericin B/posaconazole should be coadministered. Hyperbaric oxygen, Granulocyle colony stimulating factor and interferong might give some benefit, as adjunctive treatment and their role require further evaluation. Continued expansion of the wound despite broadspectrum antibiotic therapy, failure to isolate bacterial organisms and demonstration of ribbon like, aseptate hyphae in tissue section are some of features that are helpful in the early diagnosis of NF of fungal etiology. Rapid progression and unacceptably high mortality

Prevalence of Human metapneumovirus infection among patients with influenza-like illness: Report from a Tertiary Care Centre, Southern India.

Background: Human metapneumovirus (HMPV), discovered in the 21st century, has emerged as an important cause of influenza-like illness in children and adults causing mild upper respiratory tract infection to severe bronchiolitis and community-associated pneumonia. The aim of this study was to determine the prevalence of HMPV in the Union Territory of Puducherry, India, as part of National Influenza Surveillance Programme. Materials and Methods: From November 2011 to December 2013, a total of 447 nasopharyngeal samples were collected from patients with acute respiratory infections and tested for HMPV RNA by real-time polymerase chain reaction. Results: HMPV was identified in 23/447 (5%) samples with 11/23 in the age group of 14–30 years. Most of the HMPV infections were mild with no fatalities. Two patients were co-infected with the respiratory syncytial virus and one with influenza B virus. The seasonal distribution showed increasing HMPV infection cases in rainy months except for a peak in summer of 2012. Phylogenetic analysis based on the sequences of the nucleoprotein gene of one HMPV strain showed a high degree of sequence identity with Indian strains obtained during 2006 and 2011. Conclusion: This study shows that HMPV infection is more common in adults than in children. Sequence homology suggests the circulation of closely related HMPV strains within the country.

Epidemiology of influenza viruses from 2009 to 2013 – A sentinel surveillance report from Union territory of Puducherry, India

OBJECTIVE To report the findings of influenza surveillance programme from Union territory of Puducherry and to document the clinical and epidemiological data of influenza viruses over a five year period from 2009 to 2013. METHODS Respiratory samples were collected from patients with influenza-like illness from 2009 to 2013 as part of routine diagnostic and surveillance activity. Detection of pandemic influenza A (H1N1) 2009, influenza A (H3N2) and influenza B was done using Real-time PCR. RESULTS Of the total 2247 samples collected from patients with influenza-like illness during the study period 287 (12.7%) and 92 (4.0%) were positive for influenza A (H1N1) 2009 and influenza A (H3N2) respectively. A subset of 557 of these samples were also tested for influenza B and 24 (4.3%) were positive. Significantly higher positivity rate for both viruses was observed in adults when compared with children. The peak positivity of influenza A (H1N1) 2009 was observed in 2009 followed by 2012, while that of influenza A (H3N2) was more uniformly distributed with the exception of 2012. Overall mortality rate due to influenza A (H1N1) 2009 was 7.6% while it was 1% for influenza A (H3N2). Each year influenza-like illness and influenza virus activity coincided with period of high rainfall and low temperature except in the first half of 2012. CONCLUSIONS As the sole referral laboratory in this region, the data provides a comprehensive picture of influenza activity. This information will be useful in future planning of the vaccine schedule and influenza pandemic preparedness.