A study on the utility of KOH mount and HPR in the diagnosis of post COVID mucormycosis
DOI:
https://doi.org/10.18203/issn.2454-5929.ijohns20232901Keywords:
Mucormycosis, KOH mount, Histopathological examination, Nasal endoscopyAbstract
Background: Mucormycosis is a deadly disease that mostly affects the immunocompromised. Steroid therapy following COVID-19 infection has led to an alarming rise in the rates of this rare infection. Key to management of this disease is early diagnosis. The most common modalities used for diagnosis are KOH mount and histopathological examination. In our study we compare the efficacy of these two diagnostic modalities.
Methods: Nasal endoscopy was done in all suspected cases of the disease. Nasal discharge, crusts were collected in a sterile manner and sent for KOH mount examination. Specimens collected following surgical debridement was sent for HPR examination. The results of both are compared.
Results: In our study, HPR was positive in 82.2% cases while KOH mount showed positive results in 43.5% cases only.
Conclusions: Histopathology helps in confirming the diagnosis of mucormycosis. It also helps to demonstrate tissue invasion and identification of species of fungus. But it is time consuming. KOH mount examination is rapid and inexpensive but the test shows high false negative values. Thus, KOH mount examination can be used as a screening tool while histopathological examination can be used as a confirmation test for post covid mucormycosis.
References
Scott B. Otorhinolaryngology and Head and neck surgery. 8th ed. USA: Elsevier; 2012.
Bouza E, Muñoz P, Guinea J. Mucormycosis: an emerging disease?. Clin Microbiol Infect. 2006;12(7):7-23.
Ibrahim AS. Host cell invasion in mucormycosis: role of iron. Curr Opin Microbiol. 2011;14(4):406-11.
Afshar P, Larijani LV, Rouhanizadeh H. A comparison of conventional rapid methods in diagnosis of superficial and cutaneous mycoses based on KOH, Chicago sky blue 6B and calcofluor white stains. Iran J Microbiol. 2018;10(6):433-40.
Suyoso S, Noviandini A, Astari L. A comparison of the contrast stains, Chicago blue, chlorazole black, and Parker ink, for the rapid diagnosis of skin and nail infections. Int J Dermatol. 2012;51(8):935-8.
Manick DS, Vinayaraj EV, Pavavni K, Aishwarya P. A comparison of calcofluor white, potassium hydroxide, and culture for the laboratory diagnosis of superficial fungal infection. Diagn Microbiol Infect Dis. 1990;13(4):337-9.
Brettholz AM, Mccauley SO. Mucormycosis: Early Identification of a Deadly Fungus. J Pediatr Oncol Nurs. 2018;35(4):257-66.
Arunaloke C, Rachna S. Epidemiology of Mucormycosis in India. Microorganisms. 2021;9(3):523.
Wang M, Wey S, Zhang Y, Ye R, Lee AS. Role of the unfolded protein response regulator GRP78/BiP in development, cancer, and neurological disorders. Antioxid Redox Signal. 2009;11:2307-16.
Ibrahim AS, Spellberg B, Walsh TJ, Kontoyiannis DP. Pathogenesis of mucormycosis. Clin Infect Dis. 2012;54(1):S16-22.
Chakrabarti A. Epidemiology of mucormycosis in India. Curr Fungal Infect Rep. 2013;7:287- 92.
Kumar A. Fungal rhinosinusitis: microbiological and histopathological perspective. J Clin Diag Res. 2017;11(7):DC10-2.
