Using a Madurella mycetomatis‐specific PCR on grains obtained via non‐invasive fine‐needle aspirated material is more accurate than cytology

Abstract

Background: Eumycetoma is a chronic subcutaneous inflammatory fungal infection most often caused by the fungus Madurella mycetomatis. Using a species-specific PCR on DNA directly isolated from grains is currently the most reliable method for species identification. However, so far, PCR has been performed on grains obtained through deep-seated surgical biopsies, which are invasive procedures. Grains can also be obtained via ultrasound-guided fine-needle aspiration (US-FNA). Here we determined the diagnostic performance of species-specific PCRs performed on samples obtained through US-FNA. Methods:From 63 patients, US-FNA was performed to obtain eumycetoma grains; 34 patients also underwent a deep-seated biopsy. From the grains, DNA was isolated, and one pan-fungal and two M. mycetomatis-specific PCRs were performed. The sensitivity and specificity were determined.Results: Of the 63 patients who underwent US-FNA, 78% (49/63) had evidence of eumycetoma based on cytology and 93.7% (59/63) based on species-specific PCRs.In the 34 patients for whom surgical biopsies were performed as well, 31 patients had a positive PCR for M. mycetomatis when DNA was isolated from the deep-seated biopsy, and 30 had a positive PCR when DNA was obtained from the US-FNA material. This resulted in a 96.8% sensitivity, and 100% specificity with 97.1% diagnostic accuracy for PCR performed on US-FNA. Conclusion:PCR performed on the US-FNA material has a similar sensitivity and specificity as PCR performed on deep-seated biopsies. Therefore, when using PCR, a deep-seated biopsy may not be necessary to obtain grains.

Unusual manifestation of cystic mycetoma lesions: A case report

“…Culture techniques were used to isolate and grow the microorganism in a laboratory setting 4 . Fine needle aspiration cytology (FNAC) was utilized to collect samples from the affected area for microscopic examination and assessment 4,12 …”

“…This atypical presentation of infectious diseases including mycetoma highlights the need for improving the diagnostic capacity particularly in areas endemic with more than one of infectious diseases with overlapping symptoms 6,20,21 . This improvement needs to be at the education and continuous training of healthcare providers as well as the infrastructure and integrating the use of more robust diagnostic tools such as molecular and genomic sequencing in these endemic areas 12 . Healthcare providers in such settings should be highly skeptical and try to thoroughly examine their patients and carefully revising their travel and medical history.…”

“…4 Fine needle aspiration cytology (FNAC) was utilized to collect samples from the affected area for microscopic examination and assessment. 4,12 Treatment for Streptomyces somaliensis actinomycetoma typically involves a combination of antibiotherapy, including streptomycin and co-trimoxazole, which was successful in this case. The favorable outcome suggests the effectiveness of this treatment regimen.…”

Recurrent abdominal wall mass in a hepatitis B‐positive male: An unusual case of lumbar mycetoma

“…abdominal wall, atypical presentation, eumycetoma, grains of painless swelling, sinuses (abnormal openings), and discharge-containing grains. 4 However, due to the severe neglection of operational research in mycetoma, detection and diagnosis of mycetoma cases are challenging particularly when they are presented atypically. Unfortunately, most of mycetoma cases occur among poor communities in low-and middle-income countries (LMICs), where diagnostic capacity and resources are limited that makes it more challenging to prevent, diagnose, and treat.…”

“…The infection is commonly manifested at the feet and hands 3 . Eumycetoma typically presents with a classical triad of painless swelling, sinuses (abnormal openings), and discharge‐containing grains 4 . However, due to the severe neglection of operational research in mycetoma, detection and diagnosis of mycetoma cases are challenging particularly when they are presented atypically.…”