Clonal clusters and virulence factors of methicillin-resistant Staphylococcus Aureus: Evidence for community-acquired methicillin-resistant Staphylococcus Aureus infiltration into hospital settings in Chennai, South India

Background and Objective: Staphylococcus aureus is one of the major pathogens of nosocomial infections as wells as community-acquired (CA) infections worldwide. So far, large-scale comprehensive molecular and epidemiological characterisation of S. aureus from very diverse settings has not been carried out in India. The objective of this study is to evaluate the molecular, epidemiological and virulence characteristics of S. aureus in both community and hospital settings in Chennai, southern India. Methods: S. aureus isolates were obtained from four different groups (a) healthy individuals from closed community settings, (b) inpatients from hospitals, (c) outpatients from hospitals, representing isolates of hospital–community interface and (d) HIV-infected patients to define isolates associated with the immunocompromised. Antibiotic susceptibility testing, multiplex polymerase chain reactions for detection of virulence and resistance determinants, molecular typing including Staphylococcal cassette chromosome mec (SCCmec) and agr typing, were carried out. Sequencing-based typing was done using spa and multilocus sequence typing (MLST) methods. Clonal complexes (CC) of hospital and CA methicillin-resistant S. aureus (MRSA) were identified and compared for virulence and resistance. Results and Conclusion: A total of 769 isolates of S. aureus isolates were studied. The prevalence of MRSA was found to be 7.17%, 81.67%, 58.33% and 22.85% for groups a, b, c and d, respectively. Of the four SCCmec types (I, III, IV and V) detected, SCCmec V was found to be predominant. Panton-Valentine leucocidin toxin genes were detected among MRSA isolates harbouring SCCmec IV and V. A total of 78 spa types were detected, t657 being the most prevalent. 13 MLST types belonging to 9 CC were detected. CC1 (ST-772, ST-1) and CC8 (ST238, ST368 and ST1208) were found to be predominant among MRSA. CA-MRSA isolates with SCCmec IV and V were isolated from all study groups including hospitalised patients and were found to be similar by molecular tools. This shows that CA MRSA has probably infiltrated into the hospital settings.

Human leukocyte antigen (HLA) class II association in chronic hepatitis B patients with hepatocellular carcinoma in a Malay population: A pilot study

@#Asian countries account for almost three quarter of hepatocellular carcinoma (HCC) reported globally and chronic hepatitis B infection is one of the main contributors. Clinical observations show that Malay patients with chronic hepatitis B and HCC tend to have a worse outcome, when compared to other two major races in Malaysia. The objectives of this study was to determine the frequency of human leukocyte antigen (HLA) class II alleles in chronic hepatitis B patients with HCC among Malays compared to the general population to identify potential associations of HLA alleles with this disease. HLA class II typing was performed in chronic hepatitis B patients with hepatocellular carcinoma (n=12) by -polymerase chain reaction, sequence specific primer (PCR-SSP) method. There were higher allelic frequencies of certain HLA-DQB1 and HLA-DRB1 alleles; HLA-DQB1*03 (07) (41.7%), and HLA-DRB1*12 (41.7% vs 28.6%) and compared to controls (41.7% vs 29.7%). However, there was no significant statistical correlation found when compared with the normal healthy general population. This study provides an insight into the HLA Class II association with chronic hepatitis B and hepatocellular carcinoma in Malays. However, findings from this study should be validated with a larger number of samples using a high resolution HLA typing.

Role of insertion sequence element is256 as a virulence marker and its association with biofilm formation among methicillin-resistant Staphylococcus epidermidis from hospital and community settings in Chennai, South India

The objective of this study was to detect the association of biofilm formation with IS256 among clinical and carrier isolates of methicillin-resistant Staphylococcus epidermidis (MRSE). A total of 71 MRSE isolates were included in this study. Phenotypic detection of biofilm formation was done by Congo red agar method. Detection of genes associated with biofilm formation (icaAD, aap and atlE) and insertion sequence IS256 was done by polymerase chain reaction. Of the 71 MRSE isolates,19/40 (47.5%) clinical isolates from hospital settings and 11/31 (35.5%) carrier isolates from community settings respectively were found to be positive for all the three genes tested, namely, icaAD+, aap+ and atlE+ genes. Nearly 80% of clinical isolates were found to harbour IS256, whereas only 13% of community isolates harboured IS256.

Distribution of genes encoding aminoglycoside‑modifying enzymes among clinical isolates of methicillin‑resistant staphylococci.

The objective of this study was to determine the distribution of genes encoding aminoglycoside‑modifying enzymes (AMEs) and staphylococcal cassette chromosome mec (SCCmec) elements among clinical isolates of methicillin‑resistant staphylococci (MRS). Antibiotic susceptibility test was done using Kirby–Bauer disk diffusion method. The presence of SCCmec types and AME genes, namely, aac (6’)‑Ie‑aph (2’’), aph (3’)‑IIIa and ant (4’)‑Ia was determined using two different multiplex polymerase chain reaction. The most encountered AME genes were aac (6′)‑Ie‑aph (2’’) (55.4%) followed by aph (3’)‑IIIa (32.3%) and ant (4’)‑Ia gene (9%). SCCmec type I (34%) was predominant in this study. In conclusion, the aac (6’)‑Ie‑aph (2’’) was the most common AME gene and SCCmec type I was most predominant among the MRS isolates.

Endemic Indian clones of Klebsiella pneumoniae‑harbouring New Delhi metallo‑beta‑lactamase‑1 on a hybrid plasmid replicon type: A case of changing New Delhi metallo‑beta‑lactamase plasmid landscapes in India.

Purpose: blaNDM genes are MBL genes that confer resistance to carbapenems. Globally, they are associated with diverse clones and plasmids. In this study, we characterised three isolates of Klebsiella pneumoniae‑harbouring blaNDM1 from patients undergoing chronic haemodialysis and renal transplantation. Materials and Methods: 3 blaNDM1‑producing K. pneumoniae were isolated from end‑stage renal disease patients undergoing haemodialysis and renal transplantation from a nephrology unit. All the three isolates were screened for clinically relevant resistant genes. Plasmid replicon content was analysed by polymerase chain reaction based replicon typing. Conjugation assays were done using azide‑resistant Escherichia coli J53 as the recipient strain. Multilocus sequence typing and variable number tandem repeat typing were done to find the clonality. Replicon sequence based typing was attempted to find the diversity of replicon‑associated sequences in IncHI3 plasmids. Results: All the 3 blaNDM positive isolates possessed the New Delhi metallo‑beta‑lactamase‑1 (NDM‑1) allele with an IncHI3 plasmid which was not transferable in one isolate. The isolates were found to be sequence type 14 (ST14; 2 nos) and ST38 both of which were previously reported to be the NDM‑producing K. pneumoniae STs prevalent in India. Replicon sequence analysis revealed limited sequence diversity within the repHI3 and repFIB locus. Conclusion: To the best of our knowledge, this is the first report of IncHI3, a newly assigned enterobacterial plasmid incompatibility group from India. This could either be a case of importation or a widely circulating NDM plasmid type in India.

Fungal infections of the oral mucosa.

Fungal infections in humans occur as a result of defects in the immune system. An increasing emergence in oral Candidal and non-Candidal fungal infections is evident in the past decade owing to the rise in the immunodeficient and immunocompromised population globally. Oral Candidal infection usually involves a compromised host and the compromise may be local or systemic. Local compromising factors include decreased salivation, poor oral hygiene, wearing dentures among others while systemic factors include diabetes mellitus, nutritional deficiency, HIV infection/AIDS and others. Oral candidiasis is generally a localized infection and rarely appears as a systemic fungal disease whereas oral non-Candidal fungal infections are usually signs of disseminated disease. Some of the non-Candidal fungi that were once considered exotic and geographically restricted are now seen worldwide, beyond their natural habitat, probably attributed to globalization and travels. Currently infections from these fungi are more prevalent than before and they may present either as primary oral lesions or as oral manifestations of systemic mycoses. This review discusses the various predisposing factors, clinical presentations, clinical differential diagnosis, diagnosis and management of oral candidiasis, as well as briefly highlights upon a few of the more exotic non-Candidal fungi that infect the oral mucosa.

Characterization of seeds of selected wild species of rice (Oryza) stored under high temperature and humidity conditions.

Wild progenitors of rice (Oryza) are an invaluable resource for restoring genetic diversity and incorporating useful traits back into cultivars. Studies were conducted to characterize the biochemical changes, including SDS-PAGE banding pattern of storage proteins in seeds of six wild species (Oryza alta, O. grandiglumis, O. meridionalis, O. nivara, O. officinalis and O. rhizomatis) of rice stored under high temperature (45oC) and humidity (~100%) for 15 days, which facilitated accelerated deterioration. Under the treated conditions, seeds of different wild rice species showed decrease in per cent germination and concentrations of protein and starch, but increase in conductivity of leachate and content of sugar. The SDS-PAGE analysis of seed proteins showed that not only the total number of bands, but also their intensity in terms of thickness differed for each species under storage. The total number of bands ranged from 11 to 22, but none of the species showed all the bands. Similarity index for protein bands between the control and treated seeds was observed to be least in O. rhizomatis and O. alta, while the indices were 0.7 and 0.625 for O. officinalis and O. nivara, respectively. This study clearly showed that seed deterioration led to distinctive biochemical changes, including the presence or absence as well as altered levels of intensity of proteins. Hence, SDS-PAGE protein banding pattern can be used effectively to characterize deterioration of seeds of different wild species of rice.

Melioidosis.

Melioidosis is an emerging infectious disease in India acquired through percutaneous inoculation or contaminated water. Known risk factors include diabetes mellitus, renal failure, cirrhosis, and malignancy. Melioidosis presents with a febrile illness, with protean manifestations ranging from septicemia to localized abscess formation. We present the case of a 42-year-old male from a non-endemic region who presented with fever of 2 months duration, sepsis, persistent pneumonia, right hip joint pain and hepatic and splenic abscesses. Aspiration of the joint and soft tissue fluid collection and subsequent culture yielded gram negative bacilli identified as Burkholderia pseudomallei. The epidemiology, clinical features, and laboratory diagnosis of this rare infection and its treatment is reviewed.

Cystic ductal adenocarcinoma of pancreas: an unusual variant.

Cystic lesions of the pancreas are usually pseudocysts (90%); only 10% of them are cystic tumors. These cystic tumors constitute less than 10% of all pancreatic neoplasms, making them an extremely uncommon type of pancreatic malignancy. What is more important is that these tumors are very easily misdiagnosed as pseudocysts because their characteristics are very similar to those of the benign pseudocysts. This gains importance as the cystic tumors have a high cure rate and good prognosis if diagnosed and treated on time. Of all the cystic tumors, the most common are the benign serous cystadenomas, mucinous cystic tumors, intraductal papillary mucinous neoplasms etc. Ductal adenocarcinoma of pancreas presenting in cystic form is an uncommon type of cystic tumor, making it extremely rare among all pancreatic malignancies (solid or cystic). We present the following case report. The review of literature concerning the diagnosis and management has also been discussed.

Portal hypertension in sarcoid liver disease with hypomelanotic skin involvement.

Portal hypertension due to sarcoid liver disease is a rare entity. We report the case of a 50-year-old female with sarcoid liver disease leading to portal hypertension. The literature on portal hypertension due to hepatic sarcoidosis has been reviewed and the role of steroid therapy discussed.

Sialo-odontogenic cyst--a case report.

Sialo-odontogenic cyst is an uncommon cyst of odontogenic origin that occurs in the tooth bearing areas of the jaws. These lesions are histopathologically unique, biologically aggressive and may sometimes warrant distinction from central muco-epidermoid carcinoma and botryoid variant of the lateral odontogenic cyst. Sialo-odontogenic cysts tend to recur and various factors are quoted for their recurrence viz., the presence of microcysts, thin connective tissue wall, etc. We are herewith reporting a case of sialo-odontogenic cyst for its relative rarity among the odontogenic cysts.

Basaloid squamous cell carcinoma report of a case and review of literature.

Basaloid squamous cell carcinoma (BSCC) is an aggressive distinct variant of squamous cell carcinoma that mandates recognition as a separate entity owing to the difference in its clinical behaviour. Histologically this tumor can mimic other neoplasms like adenoid cystic carcinoma, neuroendocrine carcinoma and basal cell adenocarcinoma. BSCC occurs most commonly in older men and has a site predilection for the upper aero-digestive tract. We report a case of basaloid squamous cell carcinoma for its relative rarity, which was diagnosed in a 52 year old woman, with a brief review of literature.

Renal failure in a patient with primary antiphospholipid syndrome.

Antiphospholipid antibody syndrome (APLA) is a syndrome complex characterized by recurrent arterial or venous thrombosis, recurrent fetal wastage, thrombocytopenia and presence in serum of antibodies against negatively charged phospholipids like lupus anticoagulant (LA), anticardiolipin antibody (ACLA) and subgroups. These are classified further as primary (wherein this occurs in isolation) and secondary (associated with infection, drugs and malignancies). It is uncommon to find both LA and ACLA in primary APLA syndrome (unlike as in the secondary form). Renal manifestations which include renal arterial and venous occlusion and infarction and thrombotic microangiopathy have also been infrequently described. We hereby present a case of primary APLA syndrome with unusual features of LA and ACLA occurring together and also the presence of renal failure due to left renal artery thrombosis and right renal artery occlusion.

Biochemical changes of saliva in tobacco chewers tobacco smokers, alcohol consumers, leukoplakia and oral cancer patients.

Normal salivary function is considered to be critical for the maintenance of healthy oral mucosa. Oral fluids provide an easily available non-invasive for the diagnosis of a wide range of diseases and clinical situations. The present study evaluated the variations in the biochemical constituents of saliva of leukoplakia and oral cancer patients when compared with that of the control group. 90 individuals were grouped into 6 categories with 15 individuals in each group. The groups included individuals without tobacco or alcohol habits, tobacco smokers, tobacco chewers, alcohol consumers, leukoplakia and oral cancer patients. There was significant alteration in the salivary biochemical composition of leukoplakia and oral cancer patients which could be attributed to the impairment of salivary gland function caused by tobacco and alcohol usage or by the disease process itself.

Surgical treatment of total anomalous pulmonary venous connection.

Fourteen infants ranging in age from 18 days to 10 months (median age = 4 months) underwent surgical repair of total anomalous pulmonary venous connection (TAPVC) between September, 1988 and December, 1989. The anomalous drainage was supracardiac in nine, cardiac in two, infracardiac in one and mixed in one. One patient had a complex type of TAPVC. There were two hospital deaths, one a critically ill three week old infant with obstructed infracardiac TAPVC and the other with complex TAPVC. There was no late death. All twelve survivors are in NYHA functional Class 1. Postoperative echocardiography revealed unobstructed pulmonary blood flow in all of them. Surgical correction of TAPVC in infancy has been performed with gratifying results. A high index of suspicion, early diagnosis, prompt referral and an aggressive surgical approach are essential for success in this otherwise lethal condition.