Résumé
Rationale: Microbial keratitis caused by coinfection with more than one species of pathogens is a severe condition with an unfavorable prognosis. Patient concerns: An immunocompetent Nepali woman complained of pain in the left eye, redness, watering and decreased vision for 5 months. Interventions: The patient was discarded and accurately diagnosed with coinfection with Fusarium sp. and Acanthamoeba sp. The habit of washing the eyes with tap water from a domestic storage tank was the most likely source of infection since it was found to be contaminated with cysts of Acanthamoeba sp. The woman received eye drops of fluconazole and natamycin (5%), cefazoline (50 mg/mL), atropine, and tablets of itraconazole (100 mg), which were later switched to eye drops of clotrimazole (1%), natamycin (5%) and voriconazole (1%), and tablets of itraconazole. A full thickness penetrating keratoplasty was performed followed by treatment with eye drops of voriconazole (1%), natamet (5%), ofloxacin, atropine and carboxymethylcellulose for one week. Outcomes: After treatment, the condition of the patient significantly improved and was discharged one week after keratoplasty. Lessons: This is the first report of Acanthamoeba keratitis in Nepal and the first report of coinfection with Fusarium in this country and highlights the importance of early diagnosis of microbial keratitis both in single microorganism infections and coinfections, even in no contact lens wearers.
Résumé
Objective/background: The diagnosis of leprosy has been a challenge due to the low sensibility of the conventional methods and the impossibility of culturing the causative organism. In this study, four methods for Mycobacterium leprae nucleic-acid extraction from Ziehl- Neelsen-stained slides [ZNS slides] were compared: Phenol/chloroform, Chelex 100 resin, and two commercial kits [Wizard Genomic DNA Purification Kit and QIAamp DNA Mini Kit]
Methods: DNA was extracted from four groups of slides: a high-codification-slide group [bacteriological index [BI]>/=4], a low-codification-slide group [BI = 1], a negative-slide group [BI = 0], and a negative-control-slide group [BI = 0]. Quality DNA was evidenced by the amplification of specific repetitive element present in M. leprae genomic DNA [RLEP] using a nested polymerase chain reaction
Results: This is the first report comparing four different extraction methods for obtaining M. leprae DNA from ZNS slides in Cuban patients, and applied in molecular diagnosis. Good-quality DNA and positive amplification were detected in the high-codification-slide group with the four methods, while from the low-codification-slide group only the QIAGEN and phenol-chloroform methods obtained amplification of M. leprae. In the negative-slide group, only the QIAGEN method was able to obtain DNA with sufficient quality for positive amplification of the RLEP region. No amplification was observed in the negative-control slide group by any method. Patients with ZNS negative slides can still transmit the infection, and molecular methods can help identify and treat them, interrupting the chain of transmission and preventing the onset of disabilities
Conclusion: The ZNS slides can be sent easily to reference laboratories for later molecular analysis that can be useful not only to improve the diagnosis, but also for the application of other molecular techniques