Pythium keratitis in South India: Incidence, clinical profile, management, and treatment recommendation

Purpose: To study the demographic profile, clinical features, treatment outcome, and ocular morbidity of microbiologically proven Pythium keratitis in South India. Methods: A retrospective analysis of clinical records of microbiologically proven Pythium keratitis at a tertiary eye care referral center in South India from January 2016 to November 2017 was performed. Demographic details, predisposing risk factors, microbiological investigations, clinical course, and visual outcome were analyzed. Results: Seventy-one patients with microbiologically proven Pythium keratitis were identified. The mean age was 44(±18.2) years with an increase in male preponderance and 50% were farmers. Duration of delay at time of presentation to the hospital was a mean of 14(±7.2) days. The visual acuity at baseline ranged from 6/6 to no light perception (median 2.1 logMAR). A combination of 5% natamycin and 1% voriconazole was given to 42% patients, and natamycin alone was given to 39.4% patients. 1% itraconazole eye drops alone was initiated in 7 (10%) patients and 3 among this group responded. Therapeutic keratoplasty (TPK) was performed in 48 (67.6%) patients. None of the primary grafts remained clear after a period of 1 month. Twenty-six eyes (54.2%) had graft reinfection and all these eyes either developed anterior staphyloma (4) or were eviscerated (3) and 13 eyes became phthisical. The remaining 22 patients who had TPK resulted in failed graft. Among these, re-grafts were performed in 6 patients, of which 5 were doing well at the last follow-up. Conclusion: We report a large series of patients with Pythium keratitis. Promoting early and differential diagnosis, awareness of clinicians and specific treatment options are needed for this devastating corneal disease.

Fungal keratitis caused by Podospora austroamericana: A first case report

We report a case of keratitis caused by a rare fungus Podospora austroamericana. Clinical and microbiological evaluation of the corneal ulcer was done and the treatment outcome was studied. The fungus was grown from the corneal scraping, and it was identified as P. austroamericana based on DNA sequence and analysis of the internal transcribed spacer region. The patient was treated with topical azithromycin, natamycin and voriconazole. Despite maximum medical therapy, the ulcer progressed very rapidly and the patient developed panophthalmitis and evisceration of the eye had to be done. This is the first reported case of keratitis caused by P. Austroamericana.

Prevalence and antibacterial resistance patterns of extended‑spectrum beta‑lactamase producing Gram‑negative bacteria isolated from ocular infections.

Purpose: Extended‑spectrum beta‑lactamases (ESBLs) mediated resistance is more prevalent worldwide, especially among Gram‑negative bacterial isolates, conferring resistance to the expanded spectrum cephalosporins. As limited data were available on the prevalence of ESBLs in this area, the current study was undertaken to determine the prevalence, antibacterial resistance patterns, and molecular detection and characterization of ESBL encoding resistance genes among ocular Gram‑negative bacterial isolates from ocular infections. Materials and Methods: A prospective study was done on 252 ocular Gram‑negative bacterial isolates recovered from ocular infections during a study period from February 2011 to January 2014. All isolates were subjected to detection of ESBLs by cephalosporin/clavulanate combination disc test and their antibacterial resistance pattern was studied. Molecular detection and characterization of ESBL encoding blaTEM‑, blaSHV, blaOXA‑, and blaCTX‑M (phylogenetic groups 1, 2, 9, and 8/25) resistance genes by multiplex polymerase chain reaction and DNA sequence analysis. Results: Of all Gram‑negative bacteria, Pseudomonas aeruginosa (44%) was the most common strain, followed by Enterobacter agglomerans and Klebsiella pneumoniae each (10%). Among the 252, 42 (17%) were ESBL producers. The major source of ESBL producers were corneal scraping specimens, highest ESBL production was observed in P. aeruginosa 16 (38%) and Escherichia coli 7 (16.6%). Among ESBL‑producing genes, the prevalence of blaTEM‑gene was the highest (83%) followed by blaOXA‑gene (35%), blaSHV‑gene (18.5%), and blaCTX‑M‑1‑gene (18.5%) alone or together. Conclusion: The higher rate of prevalence of ESBLs‑encoding genes among ocular Gram‑negative bacteria is of great concern, as it causes limitation to therapeutic options. This regional knowledge will help in guiding appropriate antibiotic use which is highly warranted.

Comparison of bioactive ingredients in ocimum species.

With the increasing demand for health care approaches, resurgence of herbal medicines has taken up great dimensions in changing the health care scenario across the globe. However, identification of the correct species of therapeutic importance is of utmost necessity to deliver quality products to the global market. Hence, modern approach in the standardization of single herbal preparations employing sophisticated techniques is the need of the hour. The evaluation of a product in its entirety, so-called “fingerprinting” can be accomplished by appropriate methods, which may include HPLC, GC-MS, HPTLC-densitometry, FT-NIR, high-field NMR or a combination of these techniques. Using chemical fingerprinting, plants can be demarcated on the basis of their species, strain and geographical origin. Chemical fingerprinting of plants, through chromatographic fingerprinting is highly informative which includes its use as an absolute indicator of the chemical characteristics of plants. Adulterants can be distinguished even in processed samples, enabling the authentication of the drug. Herein, in the present study two varieties of Ocimum species with green and purple coloured leaves collected from Tirunelvelli district commonly known as “Tulasi” in Tamil or “Holy Basil” in English and widely used in both ayurvedic and siddha drugs was subjected to chemical fingerprinting using HPTLC and GC. Moreover, the secondary metabolities such as polyphenols, tannins, and flavonoids were quantified to check the potency of the crude drug material. The bioactive molecule such as eugenol was found to be varying in both the species and the purple variety was found to contain more of the bioactive molecules. The fingerprinting of chemical profile as well as the quantification of the bioactive molecules in the two varieties of Ocimum species exemplified that fingerprinting using analytical techniques are comprehensive and more informative to identify and authenticate the raw drug and proves to be a tool for standardization of herbal drugs.