Actinomycosis of the urinary bladder

Abstract

Actinomycosis of the urinary bladder is a rare anaerobic bacterial infection caused by Actinomyces isrealii. Initial diagnosis is often difficult and this disease is easily misdiagnosed as a urothelial or urachal tumour. The definitive diagnosis is usually made postoperatively via tissue pathology. We discuss a case of a 54-year-old male with a smoking history and a 2.5-week history of gross hematuria. Ultrasound, computed tomography and cystoscopy revealed a large inflammatory mass adherent to the right, anterior bladder wall, suggesting malignancy. Transurethral resection and histological pathology subsequently confirmed inflammatory urothelium and gram-positive bacteria consistent with actinomyces species. IntroductionActinomycosis of the urinary bladder is a rare infection caused by the anaerobic bacteria Actinomyces isrealii. Initial diagnosis is often difficult, as it mimics urothelial or urachal tumours.1,2 The definitive diagnosis is usually made postoperatively via tissue pathology. We report a case of primary bladder actinomycosis initially diagnosed as a urothelial carcinoma that subsequently underwent a transurethral resection of a bladder tumour (TURBT). Pathologic examination subsequently confirmed actinomycosis. Case reportA 54-year-old male presented with symptoms of 2.5 weeks of painless, gross hematuria, frequency, nocturia and hesitancy. He denied any history of irritative voiding symptoms. He has a medical history of diabetes, dyslipidemia, erectile dysfunction and a 10-pack/year smoking history. On physical exam, he had a benign abdominal and rectal exam.Follow-up ultrasound by the family physician revealed a 7.7 × 5.7 × 7.3 cm mass extending from the right bladder wall with vascularity on colour Doppler and possible extension through the bladder wall (Fig. 1). Cystoscopy showed a large bladder tumour involving the posterior wall. Urothelial carcinoma and urachal tumours were suspected at this time. The urine cytology was negative for malignant cells. A transurethral resection of the mass showed a high-grade invasive lesion macroscopically, but tissue diagnosis returned inflamed urothelial mucosa with colonies of gram positive bacteria morphologically consistent with actinomyces species (Fig. 2).Based on the pathology report, a computed tomography (CT) scan was ordered to assess for the extent of infection, inflammation and lymph node involvement. Imaging showed extensive inflammatory thickening of the bladder wall and broad-based mass on the right, anterior wall with perivesical fat involvement tracking in a cephalad direction (Fig. 3).Treatment with high-dose amoxicillin was carried out for 3 months. Follow-up CT and cystoscopy post-treatment showed residual mild inflammation and edema on the right posterior bladder wall with vast improvement over previous investigations (Fig. 4). Another 3-month regimen of amoxicillin was prescribed with instructions for follow-up imaging. Discussion PathophysiologyActinomycosis is a chronic infectious disease with widespread anatomical distributi...

The Pathogenic Role of Actinomyces spp. and Related Organisms in Genitourinary Infections: Discoveries in the New, Modern Diagnostic Era

“…In case of urinary retention, the abnormal flow of urine allows for bacteria to adhere to the epithelial lining and subsequently infect the urinary tract [120,121]. Thus, it is plausible that a similar mechanism contributes to the pathological processes associated with urinary tract actinomycosis [122]. The pathogenesis of primary bladder actinomycosis is unclear, but could be due to cryptic locations, and usually mimics bladder carcinoma; the lesions may invade adjacent organs such as the uterus or the sigmoid colon [123].…”

Network-Based Differences in the Vaginal and Bladder Microbial Communities Between Women With and Without Urgency Urinary Incontinence

“…Among the top genera most associated with Aerococcus were Actinomyces , Gardnerella , Prevotella , and Bacteroides. Actinomyces species have been reported as associated with genitourinary actinomycosis (particularly in the setting of IUD use) and urinary tract actinomycosis ( Huang and Al-Essawi, 2013 ; García-García et al., 2017 ). Gardnerella and Prevotella are well-known pathogens involved in bacterial vaginosis ( Randis and Ratner, 2019 ).…”

Clinical features of actinomycosis: A 20-year experience of a single institute in Southern China

“…Such infections originate from infected adjacent tissues or, less frequently, following hematogenous dissemination. Infections of the urogenital tract [13], eye [14], skin [15], and disseminated disease [3] focalized in the central nervous system (CNS) [16] are rare; a case of penile actinomycosis has also been reported [17]. Actinomyces spp are very susceptible to a wide variety of antimicrobials, thus relatively few doses may render cultures negative.…”