Colloidal gold based immunochromatographic detection of Mycoplasmopsis synoviae infection and its prevalence in avian species of Karachi, Pakistan.

Avian mycoplasmosis is an infection that commonly prevails in birds, particularly in poultry chickens. Among mycoplasmosis causing organisms, Mycoplasmopsis synoviae is a predominant and lethal pathogen to the aves. Considering the increased incidence of infections by M. synoviae, the prevalence of M. synoviae was deduced in poultry chickens and fancy birds of Karachi region. The lungs and tracheal samples from chicken and dead fancy birds and swab samples from live fancy birds were collected and investigated by amplifying 16 s rRNA gene of M. synoviae. Biochemical characteristics of M. synoviae was also evaluated. Furthermore, surface-associated membrane proteins, that represent key antigens for diagnosis of M. synoviae infection was extracted by Triton X- 114 method. Results showed that M. synoviae was detected more frequently in lungs than in trachea, that could be due to its invasion capacity and tissue affinity. SDS PAGE analysis of extracted membrane proteins showed two prominent hydrophobic proteins of different molecular mass including proteins of 150 and 50 kDa. Protein of 150 kDa was purified by size exclusion chromatography and it exhibited agglutinogen activity. Purified protein was used in the development of one-step immunochromatographic (ICT) assay for the detection of antibodies against M. synoviae using gold nanoparticles coated with polyclonal antibodies. Low levels of antibodies were detected by the developed ICT kit, which has 88% sensitivity with 92% specificity.

A cross sectional study to observe the diversity of fungal species in Onychomycosis isolated from a tertiary care hospital in Karachi.

OBJECTIVE: To study the frequency and diversity of fungi involved in onychomycosis. METHODS: The cross-sectional study was conducted from February 2018 to February 2019 at the Department of Microbiology, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi, and the University of Karachi. Specimens were taken from patients suffering with onychomycosis attending the Dermatology Department of Jinnah Postgraduate Medical Centre and were processed for the isolation of fungi. Specimens were processed for the diagnosis by potassium hydroxide mount for microscopic evaluation and mycological culture to determine the type of fungus involved in onychomycosis. Fungi were isolated using Sabouraud Dextrose Agar with antibiotics cycloheximide and chloramphenicol, and without antibiotics. Plates were observed for the growth periodically until 4th week. Appearance of any colony was studied further for identification on the basis of cultural characteristics and microscopy. Precise identification of Candida species was done. RESULTS: Of the 230 samples, 85(36.96%) were from males and 145(63.04%) from females. Potassium hydroxide mount showed fungal element in 134(58.26%) specimens, while in 111(48.26%) patients the fungal culture was positive. Nine (3.9%) cases were culture-positive but potassium hydroxide-negative, while among the 134(58.26%) potassium hydroxide-positive cases, 32(23.9%) were culture-negative.