Pathological Abnormalities Observed on Ultrasonography among Fishermen Associated with Male Genital Schistosomiasis (MGS) along the South Lake Malawi Shoreline in Mangochi District, Malawi

Abstract

Schistosome eggs cause granulomata and pathological abnormalities, detectable with non-invasive radiological techniques such as ultrasonography which could be useful in male genital schistosomiasis (MGS). As part of our novel MGS study among fishermen along Lake Malawi, we describe pathologies observed on ultrasonography and praziquantel (PZQ) treatment over time. Fishermen aged 18+ years were recruited, submitted urine and semen for parasitological and molecular testing, and thereafter, transabdominal pelvic and scrotal ultrasonography, assessing pathologies in the prostate, seminal vesicles, epididymis and testes. Standard PZQ treatment and follow-up invitation at 1-, 3-, 6- and 12-months' time-points were offered. A total of 130 recruited fishermen underwent ultrasonography at baseline (median age: 32.0 years); 27 (20.9%, n = 129) had S. haematobium eggs in urine (median: 1.0 egg/10 mL), 10 (12.3%, n = 81) in semen (defined as MGS, median: 2.9 eggs/mL ejaculate) and 16 (28.1%, n = 57) had a positive seminal Schistosoma real-time PCR. At baseline, 9 fishermen (6.9%, n = 130) had abnormalities, with 2 positive MGS having prostatic and testicular nodules. Fewer abnormalities were observed on follow-up. In conclusion, pathologies detected in male genitalia by ultrasonography can describe MGS morbidity in those with positive parasitological and molecular findings. Ultrasonography advances and accessibility in endemic areas can support monitoring of pathologies' resolution after treatment.

Keywords: MGS; epididymis; prostate; seminal vesicles; testis; ultrasonography.

Figure 1

Schematic map of Study area showing health facilities along Lake Malawi. (The study map was produced by Sekeleghe Kayuni (on 4 August 2019), while the maps of Africa and Malawi were reproduced from the maps at the Central Intelligence Agency (CIA) website, public domain: https://www.cia.gov/library/publications/the-world-factbook/attachments/locator-maps/MI-locator-map.gif accessed on 4 August 2019 and https://www.cia.gov/library/publications/the-world-factbook/attachments/maps/MI-map.gif accessed on 4 August 2019).

Figure 2

The portable Chison Q5 ultrasound scanner in an examination room.

Figure 3

Ultrasonographic images of an MGS positive study participant with abnormalities in the bladder and prostate at Baseline. (A,B). Irregular urinary bladder wall and severe focal thickness, measuring up to 13.6 mm. (C). Normal symmetrical seminal vesicles. (D). Prostate with abnormal irregular outline, but normal volume of 18.3 mL. (E,F). Hyperechoic nodule in the prostate, measuring 11.4 mm by 16.2 mm.

Figure 4

Images of the POC-PSA test conducted on participants with Prostate abnormalities. (A,E). Strong positive POC-PSA with no urine or semen eggs and no abnormalities. (B). Negative POC-PSA with semen real-time PCR (Ct-value: 25.4), irregular prostate outline and hyperechoic nodule. (C). Negative POC-PSA with no urine eggs, but had grossly irregular, enlarged prostate (61.3 mL), abnormal epididymis and bilateral hydrocele. (D). Negative POC-PSA with no urine or semen eggs, negative real-time PCR but had irregular, enlarged prostate (39.1 mL).

Figure 5

Ultrasonographic image of study participant with left testicular nodule at baseline.