Bladder, ureter & renal pelvis

Cystitis

Encrusted cystitis



Last author update: 7 October 2022
Last staff update: 7 October 2022

Copyright: 2020-2022, PathologyOutlines.com, Inc.

PubMed Search: Encrusted cystitis bladder

Bohdan Zoshchuk, M.D.
Y. Albert Yeh, M.D., Ph.D.
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Cite this page: Zoshchuk B, Rinehouse N, Yeh YA. Encrusted cystitis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/bladderencrustedcystitis.html. Accessed December 10th, 2022.
Definition / general
Essential features
Terminology
ICD coding
  • ICD-10: N30.21 - other chronic cystitis with hematuria
  • ICD-11: GC00.1 - infectious cystitis
  • ICD-11: GC00.Y - other specified cystitis
Epidemiology
  • Incidence: 0.016 - 0.32% of clinical samples for bacterial cultures (Infect Drug Resist 2015:21;8:129)
  • 0.6% occurred in patients who received renal transplant (Front Med (Lausanne) 2021;7:609024)
  • Age and gender:
  • Natural colonizer of human skin and urinary tract
  • Transmitted by air or nosocomially (Infect Drug Resist 2015:21;8:129)
  • Risk factors (Front Med (Lausanne) 2021;7:609024):
    • Urological instrumentation (bladder catheterization)
    • Surgical or endoscopic procedure (cystoscopy, cystography)
    • Urological disease (urinary tract infections, intravesical mitomycin or bacillus Calmette-Guérin [BCG] instillations, radiation cystitis, drug induced cystitis, urolithiasis, malakoplakia, neurogenic bladder)
    • Chronic debilitating disease (diabetes, chronic renal insufficiency, liver cirrhosis, neurological disease, prolonged hospitalization)
    • Broad spectrum antibiotic therapy
    • Immunocompromised status (kidney transplantation, cancer, cytotoxic drug treatment, immunosuppressive therapy)
Sites
Pathophysiology
  • Urinary colonization and adherence to host tissue:
    • Colonization: asymptomatic, positive urine cultures
    • Adherence mediated by adhesive pili that covalently anchored to Corynebacterium cell wall (Front Med (Lausanne) 2021;7:609024)
  • Formation of struvite and carbonated apatite crystals
    • Corynebacterium urealyticum has strong urease activity that hydrolyses urea (pH ≥ 7.1) leading to formation of NH3 and CO2 (see diagram 1)
    • NH3 combines with H+ to form NH4+
    • In alkaline urine, NH4+ reacts to Mg2+ and PO43-, leading to formation of struvite (magnesium ammonium phosphate, NH4MgPO4.6H2O)
    • In alkaline urine, CO2 converts to bicarbonate HCO3- which reacts to Ca2+ and PO43-, leading to formation of calcium phosphate crystals (carbapatite, Ca10(PO4)6CO3) (Front Med (Lausanne) 2021;7:609024)
    • Infected urine saturates with struvite and calcium phosphate and precipitates, resulting in bladder wall incrustation in a suitable urothelial environment injured by inflammation, malignancy, ischemia or urological instrumentation
  • Adherence to medical device:
Etiology
  • Corynebacterium urealyticum (formerly coryneform CDC group D2)
    • Gram positive, aerobic, urease positive, pleomorphic, lipophilic, acid fast, non-spore forming, asaccharolytic and usually multidrug resistant bacillus (Clin Microbiol Infect 2008;14:632)
    • Common skin colonizer and opportunistic pathogen mainly detected in the groin area in hospitalized elderly patients receiving broad spectrum antibiotics
    • Pathological even if colony forming units (CFU) < 100,000/mL on urine cultures (Front Med (Lausanne) 2021;7:609024)
    • Highly susceptible to norfloxacin and vancomycin (J Clin Microbiol 1985;21:788)
  • Other bacteria: Ureaplasma urealyticum, Proteus vulgaris, Streptococcus haemolyticus, Streptococcus viridans, Staphylococcus species, Pseudomonas aeruginosa, Escherichia coli, Corynebacterium gluconolyticum, Arcanobacterium pyogene (Front Med (Lausanne) 2021;7:609024)
Diagrams / tables

Images hosted on other servers:

Struvite and carbonated apatite

Flowchart of diagnosis

Clinical features
  • Fever (25 - 50%), urinary frequency, urgency, stranguria, nycturia, suprapubic / pelvic pain, vesical tenesmus, costovertebral angle tenderness, dysuria (Br J Urol 1993;72:571)
  • Less often nausea, anorexia and weight loss
  • Commonly macroscopic hematuria detected in 75 - 100%
  • Urination of mucus, purulent debris, calcified necrotic debris, gravel or renal stones
Diagnosis
  • Clinical manifestations: urinary frequency, urgency, dysuria
  • Past clinical history and predisposing conditions
  • Urinalysis: alkaline urine (pH > 7.0), leukocytes
  • Urine microbiological cultures: positive for urease producing bacteria, commonly Corynebacterium urealyticum (J Med Microbiol 1998;47:79)
  • Radiological findings: thickening bladder wall with calcifications (Xray, ultrasound, CT scan)
  • Other conditions in the differential diagnosis of urinary tract encrustations or calcifications need to be excluded by means of cystoscopy and histopathological examination (Front Med (Lausanne) 2021;7:609024)
  • Cystoscopic examination: ulcerations, erythema, increased vascularity, yellow or white plaques firmly attached to the bladder mucosa (World J Clin Cases 2020;8:4234)
  • See diagram 2
Laboratory
  • Urinalysis:
    • Urinary ammonia-like odor
    • Alkaline urine (pH > 7.0)
    • Microscopic hematuria
    • Pyuria
    • Struvite crystalluria
    • Gritty calcified debris or stones
    • Mucopurulent debris (Front Med (Lausanne) 2021;7:609024)
  • Microbiological culture:
    • Conventional urine cultures often negative for Corynebacterium urealyticum
    • No specific transport media
    • Prolonged incubation in 5% CO2, 35 - 37 °C, for 48 - 72 hours
    • Nonselective media including blood agar or cysteine lactose electrolyte deficient agar
    • Selective media including lipid enriched peptone based CBU agar or Loeffler serum medium (3 parts of sheep or horse serum plus 1 part of glucose broth) (J Med Microbiol 1998;47:79, Infect Drug Resist 2015:21;8:129)
Radiology description
Radiology images

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Linear calcifications

Irregular calcifications

Case reports
Treatment
  • Endoscopic mucosal resection of encrusted calcifications
  • Urinary acidification: acetohydroxamic acid
  • Systemic glycopeptides antibiotic (especially teicoplanin and vancomycin) therapy for a few weeks to a few months (Front Med (Lausanne) 2021;7:609024)
Clinical images

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Multiple thin calcifications

Microscopic (histologic) description
  • May form 3 distinct layers
  • First superficial layer:
    • Ulceration and necrotic urothelial tissue
    • Calcified necrotic debris (demonstrated by von Kossa staining)
    • Degenerative changes with squamous metaplasia in nonaffected urothelium
  • Second layer:
    • Lamina propria with edematous and granulation tissue
    • Inflammatory infiltrate with lymphocytes, plasma cells, neutrophils, sometimes granulomas
    • Less often eosinophils, mast cells, fibroblasts and histiocytes
    • Small vascular thrombosis (may present)
    • Crystal deposition
    • Microabcesses with bacterial microcolonies (may present)
  • Third layer:
Microscopic (histologic) images

Contributed by Bohdan Zoshchuk, M.D. and Y. Albert Yeh, M.D., Ph.D.
Dystrophic calcifications

Dystrophic calcifications

Encrusted calcifications

Encrusted calcifications

Encrusted necrotic debris

Encrusted necrotic debris

Encrusted calcified fragments

Encrusted calcified fragments

Calcified plaques

Calcified plaques

Calcifications and chronic inflammation

Calcifications and chronic inflammation


Encrustations and fibrin

Encrustations and fibrin

Calcifying encrustations

Calcifying encrustations

Calcifications and giant cells

Calcifications and giant cells

Calcifications in fibrotic stroma

Calcifications in fibrotic stroma

Calcium salts

Calcium salts

Positive stains
Negative stains
Electron microscopy description
Electron microscopy images

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Calcifying nanoparticles

Molecular / cytogenetics description
Sample pathology report
  • Urinary bladder, biopsy:
    • Bladder tissue with acute and chronic inflammation and abundant calcification (see comment)
    • Comment: The urothelial mucosa shows ulcerations and extensive calcified necrotic debris admixed with many multinucleated giant cells. Granulation tissue with acute and chronic inflammatory infiltrate, eosinophils and fibrin deposits are present. Clinical correlation with urinalysis and microbiological culture is highly recommended. These findings are consistent with encrusted cystitis in the right clinical context.
Differential diagnosis
Board review style question #1

A bladder biopsy is shown above from a male patient with a history of bladder instrumentation. The entity depicted above is characterized by deposition of inorganic salts within injured urothelial mucosa due to the action of the urea splitting bacteria. What is the diagnosis?

  1. Emphysematous cystitis
  2. Encrusted cystitis
  3. Eosinophilic cystitis
  4. Interstitial cystitis
  5. Malakoplakia
Board review style answer #1
B. Encrusted cystitis

Comment Here

Reference: Encrusted cystitis
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