Prevalence and antimicrobial profile of Shigella isolates in a tertiary care hospital of North Karnataka: A 12-year study.

Context: Shigella is a common cause of bacillary dysentery. Although it is reported worldwide, the majority of the infections are seen in developing countries with Shigella flexneri being the most common isolate. Prevalence of Shigella species and their antibiotic susceptibility profiles vary according to geographic area and season. Aims: In the present study, the epidemiology and antimicrobial profile of Shigella from stool samples received at our hospital for a period of 12 years (January 2006 to December 2017) was evaluated. Subjects and Methods: A total of 4578 stool samples were collected from the cases of acute gastroenteritis and diarrhoea. Samples were processed for culture and sensitivity according to standard microbiological techniques. The presumptive identification of Shigella species was done using standard conventional biochemical tests and confirmed using antisera. Results: A total of 189 (4.2%) samples yielded Shigella spp. Isolation of Shigella spp. were more frequent from males (58.2%). S. flexneri was the commonest species isolated (47.6%) followed by Shigella sonnei(11.6%), Shigella dysenteriae (4.2%) and Shigella boydii (2.1%). Non-typeable Shigella was commonly recovered. The isolates showed high resistance to ampicillin (76.7%) and co-trimoxazole (75%) while highest susceptibility was observed to ceftriaxone (79.2%). Conclusions: S. flexneri was the most prevalent species isolated at this centre. Shigella isolates from the study showed alarming resistance to recommended antibiotics. Non-typeable Shigella accounted for 34.4% isolates. Molecular discrimination between Shigella and Escherichia coli is essential.

Trend of human brucellosis over a decade at tertiary care centre in North Karnataka.

BACKGROUND: Brucellosis is an important zoonotic disease. India having a major agrarian population is expected to have a higher prevalence. However, due to lack of laboratory facility or awareness among clinicians, the disease is largely underreported. The aim of this study was to know the prevalence and trend of human brucellosis over a decade, in patients attending a teaching hospital in North Karnataka, and to understand their geographical distribution. MATERIALS AND METHODS: The study was conducted from January 2006 to December 2015 at a tertiary care teaching hospital in North Karnataka. A total of 3610 serum samples were evaluated from suspected cases of brucellosis. All serum samples were initially screened by Rose Bengal plate test, and positive samples were further analysed by Serum agglutination test (SAT) using standard Brucella abortus antigen from Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India. A titre above or equal to 1:80 IU/ml was considered as positive. Demographic data such as age, sex and native place of these patients were also analysed. RESULTS: We observed that human brucellosis is present in North Karnataka. The overall seropositivity of brucellosis in suspected cases was 5.1%. The positive titres ranged from 1:80 to 163,840 IU/ml. The majority of the patients were from Gadag, Koppal and Haveri districts of North Karnataka. CONCLUSION: Our study confirms the presence of human brucellosis in the northern part of Karnataka. Further studies to understand the prevalence of animal brucellosis in these areas will help in implementing prevention measures.

Comparative study of Candida in oral submucous fibrosis and healthy individuals / Estudo comparativo de Candida em fibrose submucosa oral e indivíduos saudáveis

PURPOSE: Oral submucous fibrosis (OSMF) is a high-risk precancerous condition that predominantly affects Indian youngsters due to the habit of gutkha chewing. Candida may play a role in the etiopathogenesis of premalignant and malignant lesions. The aim of this study is to compare the incidence, intensity, and species of Candida found in OSMF patients and healthy individuals. METHODS: This study included 20 OSMF patients and 20 healthy controls. A detailed history of each patient was recorded along with a clinical examination. Samples were collected with the oral rinse technique and cultured on Sabouraud's agar medium. The isolated yeast species were counted and identified based on Gram staining, a germ tube test, chlamydospore formation and a sugar assimilation test. RESULTA: In total, 40 percent of OSMF patients and 15 percent of healthy controls yielded Candida organisms on culture. C. albicans was the predominant species isolated, but C. krusei and C. tropicalis were also identified. Gender, gutkha habit and clinical staging had no influence on the candidal carriage in OSMF patients. CONCLUSION: The incidence and intensity of Candida (primarily C. albicans) was greater in OSMF patients than in healthy controls, but these findings were within the normal limit (3-47 percent). Therefore, Candida may not be an etiologic factor in malignant transformation. However, controversy still exists over whether the chewing of betel quid in cases of OSMF has an inhibitory effect or promotes the adherence and invasion of Candida.

OBJETIVO: Fibrose submucosa oral (FSO) é uma condição pré-maligna de alto risco que predominantemente afeta jovens da Índia devido ao hábito de mascar 'gutkha'. Candida pode ter um papel importante na etiopatogenia de lesões pré-malignas e malignas. O objetivo deste estudo foi comparar a incidência, intensidade e Candida spp encontradas em pacientes com FSO e em indivíduos saudáveis. METODOLOGIA: Este estudo incluiu 20 pacientes com FSO e 20 controles saudáveis. Obteve-se de cada sujeito uma história detalhada e exame clínico. As amostras foram coletadas com uma técnica de enxágue bucal e cultivadas em meio Agar Sabouraud. As espécies isoladas foram contadas e identificadas com base em coloração Gram, teste de tubo de ensaio e teste de assimilação de açúcar. RESULTADOS: No total, 40 por cento dos pacientes com FSO e 15 por cento dos controles saudáveis apresentaram resultado positivo de cultura para Candida. C. albicans foi a espécie predominante isolada, mas C. krusei e C. tropicalis também foram identificados. O sexo, hábito de mascar 'gutkha' e estadiamento clínico não influenciaram a presença de fungos nos pacientes com FSO. CONCLUSÃO: A incidência e intensidade de Candida (primariamente C. albicans) foi maior nos pacientes com FSO que nos sujeitos controle, mas estes achados estavam dentro dos limites normais (3-47 por cento). Portanto, Candida pode não ser um fator etiológico na transformação maligna. Entretanto, ainda há controvérsias se o hábito de mascar 'betel' em casos de FSO teria um efeito inibidor ou promoveria a aderência e invasão de Candida.

Purification and characterization of a mitogenic lectin from cephalosporium, a pathogenic fungus causing mycotic keratitis.

Ophthalmic mycoses caused by infectious fungi are being recognized as a serious concern since they lead to total blindness. Cephalosporium is one amongst several opportunistic fungal species implicated in ophthalmic infections leading to mycotic keratitis. A mitogenic lectin has been purified from the mycelia of fungus Cephalosporium, isolated from the corneal smears of a keratitis patient. Cephalosporium lectin (CSL) is a tetramer with subunit mass of 14 kDa, agglutinates human A, B, and O erythrocytes, and exhibits high affinity for mucin compared to fetuin and asialofetuin but does not bind to simple sugars indicating its complex sugar specificity. CSL showed strong binding to normal human peripheral blood mononuclear cells (PBMCs) to elicit mitogenic activity. The sugar specificity of the lectin and its interaction with PBMCs to exhibit mitogenic effect indicate its possible role in adhesion and infection process of Cephalosporium.

Comparative study of adherence of oral Candida albicans isolates from HIV sero-positive individuals and HIV sero-negative individuals to human buccal epithelial cells.

AIM: Candida albicans occurs as a commensal of the gastrointestinal tract. Under predisposing conditions, candida can produce a broad array of infections. HIV seropositive individuals show increased oral colonization compared to the HIV seronegative healthy individuals. C. albicans shows a variety of pathogenic factors. We have studied one such factor here; the adherence property of C. albicans isolated from HIV seropositive individuals and HIV seronegative to Human Buccal Epithelial Cells (HBEC) of normal healthy individuals. MATERIALS AND METHODS: Concentrated oral rinse specimen were collected from 50 healthy volunteers (control group) and 25 HIV positive individuals (test group) and used for isolation of C. albicans. Adherence assay was done using C. albicans isolates from both groups on HBEC collected from HIV sero-negative, normal individuals. The adherence assay method described by Kimura and Pearsall was used with minor modification. STATISTICAL ANALYSIS USED: The results of Adhesion assay were subjected to statistical analysis using student "t" test. RESULTS: C. albicans isolated from both the groups were tested for their adherence property to normal HBEC. The isolates from test group showed more adherence to HBEC compared to those of the control group, with average rate of adherence being 56.6%. The control group showed average adherence rate of 29.1%. This was statistically significant with p value equal to 0.05. CONCLUSION: C. albicans from HIV infected individuals showed significant rise in degree of adhesion to the buccal epithelial cells than the isolates from healthy controls, suggesting the enhancement of virulence factors such as adherence in the presence of predisposing condition.

Isolation of Salmonella enterica serotype Isangi from a suspected case of enteric encephalopathy.

Nontyphoidal salmonella species are thought to be potentially infectious to humans and many are documented to cause human diseases. We isolated S. Isangi from the blood of a 30-year-old man with complaints of diarrhoea, fever, and altered sensorium. The serotype of the isolate was confirmed at National Salmonella Centre (Vet.), Division of Bacteriology and Mycology, Indian Veterinary Research Institute, Izzatnagar, India. The isolate was not an extended spectrum beta-lactamase (ESBL) producer and the patient responded well to ceftriaxone. We reviewed the literature concerning infections caused by salmonella; however, did not find any report related to S. Isangi infection in human beings from India.

Phenotypic detection of inducible clindamycin resistance among Staphylococcus aureus isolates by using the lower limit of recommended inter-disk distance.

CONTEXT: Clindamycin is one of the important alternative antibiotics in the therapy of Staphylococcus aureus, particularly in methicillin-resistant S. aureus (MRSA) infections. Inducible clindamycin resistance (iMLS B--inducible Macrolide-Lincosamide-Streptogramin B resistance) is a critical factor in antimicrobial susceptibility testing. AIMS: To know the rate of inducible clindamycin resistance among clinical isolates of Staphylococcus aureus in our hospital by Disk approximation test (D-test) using the average recommended inter-disk distance and comparing the results with that of D-test using the lower limit of recommended inter-disk distance. MATERIALS AND METHODS: A total of 51 erythromycin-resistant and clindamycin-susceptible S. aureus isolates were subjected to disk approximation testing with 21 +/- 1 mm and 15 mm edge-to-edge distance between the clindamycin and erythromycin disks. STATISTICAL METHODS: Z-test levels. RESULTS: Among 51 erythromycin-resistant and clindamycin-susceptible S. aureus isolates, 25 (49%) were recorded as inducible clindamycin resistant by D-test with 21 +/- 1 mm edge-to-edge distance between the clindamycin and erythromycin disks. When we re-tested all the 51 strains by D-test with 15 mm inter-disk distance, we identified 14% more iMLS B strains previously reported as D-test negative. Z-test for MRSA indicates that 15 mm edge-to-edge distance has significant advantage. CONCLUSIONS: Since the incidence of inducible clindamycin resistance is high (63% in our study), accurate identification of inducible clindamycin resistance is important to prevent therapeutic failure in infections caused by these strains. We suggest the use of D-test with 15 mm edge-to-edge inter-disk distance for detecting iMLS B .

Oratest:--a simple, chair-side caries activity test.

Caries activity tests are an essential part of any programme concerned with the study or treatment of dental caries. Most of the caries activity tests require expensive kits or specially prepared media or facilities for incubation which limits their use in clinical practice. The present study sample consisted of twenty five children with dental caries and twenty five controls, free of caries, gingivitis and other oral ailments. The test is simple and consists of rinsing the mouth with 10 ml of sterile milk, 3 ml of which is mixed with 0.12 ml of 0.1% methylene blue dye and observed for colour change. The present study demonstrated the potential uses of this test in a pediatric dental clinic setup.