Model Answer
0 min readIntroduction
Acute urinary retention (AUR) is the sudden inability to voluntarily void urine. Haematuria, the presence of blood in the urine, alongside AUR, raises concern for underlying urological pathology. In an elderly male, the most common cause of AUR is benign prostatic hyperplasia (BPH), often complicated by bladder outlet obstruction. However, other etiologies must be considered. A per rectal examination revealing a hard, nodular prostate strongly suggests prostatic enlargement, potentially malignant. Prompt and accurate diagnosis is crucial for appropriate management and improved patient outcomes.
Diagnosis
The most likely diagnosis, given the clinical presentation of acute urinary retention, haematuria, and a hard, nodular prostate on per rectal examination, is prostatic enlargement secondary to either Benign Prostatic Hyperplasia (BPH) or Prostate Cancer. The haematuria could be due to vascular congestion within the enlarged prostate, irritation of the bladder mucosa from the catheter, or, more concerningly, a sign of malignancy.
Differential Diagnoses
While BPH or prostate cancer are most probable, other possibilities include:
- Prostatitis: Inflammation of the prostate, though typically presents with pain and fever.
- Urethral Stricture: Narrowing of the urethra, less likely given the prostate findings.
- Bladder Neck Obstruction: Less common in isolation.
- Neurogenic Bladder: Less likely without a history of neurological disease.
Investigations
Phase 1: Initial Assessment & Basic Investigations
These investigations are aimed at confirming the diagnosis, assessing renal function, and ruling out acute complications.
- Urinalysis & Microscopy: To confirm haematuria, rule out infection (pyuria), and assess for malignant cells.
- Serum Creatinine & Electrolytes: To assess renal function, which may be impaired due to post-renal acute kidney injury.
- Prostate-Specific Antigen (PSA): A crucial marker for prostate cancer. Elevated levels warrant further investigation.
- Complete Blood Count (CBC): To assess for anaemia (due to chronic blood loss) and signs of infection.
- Post-Void Residual (PVR) Volume: Measured via ultrasound. Although the patient has acute retention, this is useful post-catheterization to assess bladder emptying.
Phase 2: Imaging & Further Evaluation
These investigations help to characterize the prostate and rule out other causes of haematuria.
- Transrectal Ultrasound (TRUS): Provides detailed images of the prostate, including size, shape, and echogenicity. Can guide prostate biopsies.
- Multiparametric MRI (mpMRI) of the Prostate: Increasingly used as a first-line imaging modality for suspected prostate cancer. Provides functional information about the prostate, improving diagnostic accuracy.
- Cystoscopy: Allows direct visualization of the urethra and bladder neck, assessing for obstruction, inflammation, or tumours.
- Upper Tract Imaging (CT Urographram or Renal Ultrasound): To rule out upper tract obstruction or other causes of haematuria (e.g., renal cell carcinoma).
Phase 3: Biopsy & Histopathology
If malignancy is suspected based on PSA levels, imaging findings, or clinical suspicion, a biopsy is necessary.
- Prostate Biopsy: Typically performed transrectally under ultrasound guidance. Multiple cores are taken from different areas of the prostate.
- Histopathological Examination: Biopsy samples are examined under a microscope to determine the presence and grade of cancer.
| Investigation | Purpose | Advantages | Disadvantages |
|---|---|---|---|
| PSA | Screening for prostate cancer | Relatively inexpensive, widely available | Can be elevated in BPH and prostatitis; not specific for cancer |
| TRUS | Prostate imaging, biopsy guidance | Real-time imaging, allows for targeted biopsy | Can be uncomfortable, risk of infection |
| mpMRI | Prostate imaging, cancer detection | High sensitivity and specificity for cancer detection | More expensive than TRUS, availability may be limited |
Conclusion
In conclusion, a 75-year-old male presenting with acute urinary retention and haematuria with a hard, nodular prostate on PR examination necessitates a thorough investigation to differentiate between BPH and prostate cancer. A stepwise approach, starting with basic investigations and progressing to imaging and biopsy as indicated, is crucial. Prompt diagnosis and appropriate management are essential to alleviate symptoms, prevent complications, and improve the patient’s quality of life. The presence of haematuria warrants a high index of suspicion for malignancy.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.