A young lady presents with symptoms of Urinary Tract Infection. All of the following findings on a midstream urine sample suppo the diagnosis of ‘Uncomplicated Acute Cystitis’, EXCEPT:
Uncomplicated acute cystitis is usually caused by E. coli, right? The main symptoms are dysuria, frequency, urgency. The urine sample would typically show pyuria (white blood cells), bacteria, and possibly nitrites. Also, the presence of red blood cells might be there due to inflammation. So, the EXCEPT question is looking for something that's not a usual finding here.
The options are A to D, but they're not provided. Wait, the user left them blank. Hmm, maybe they forgot to include the options. But the correct answer is given as "D. Presence of dysmorphic red blood cells". Let me think. Dysmorphic RBCs are usually seen in glomerulonephritis because the RBCs are damaged as they pass through the glomerular basement membrane. In a UTI, RBCs would be intact, so dysmorphic RBCs would be abnormal. So that would be the exception here.
Other findings supporting cystitis would include pyuria (WBCs), bacteria on Gram stain, nitrites from bacterial metabolism (if the bacteria produce nitrate reductase), and maybe some RBCs. But dysmorphic RBCs point to a different pathology, like glomerular disease. So the presence of dysmorphic RBCs would not support a UTI, making option D the correct answer here.
Wait, but let me double-check. What about the other options? If the other options are things like WBCs, bacteria, or nitrites, then those are all supportive. So the EXCEPT is D. That makes sense. The key is that dysmorphic RBCs indicate a glomerular source, not a lower UTI. So the correct answer is D.
**Core Concept**
Uncomplicated acute cystitis is a lower urinary tract infection typically caused by *E. coli*. Diagnostic criteria include symptoms like dysuria, urgency, and pyuria, with specific urinary findings such as bacteria, leukocytes, or nitrites. Dysmorphic red blood cells (RBCs) are **not** typical in this condition.
**Why the Correct Answer is Right**
Dysmorphic RBCs are characteristic of **glomerular injury** (e.g., glomerulonephritis), where RBCs are distorted as they pass through a damaged glomerular basement membrane. In uncomplicated cystitis, RBCs (if present) are usually intact ("normal morphology") due to inflammation in the bladder or urethra. This distinction is critical for differentiating glomerular vs. non-glomerular hematuria.
**Why Each Wrong Option is Incorrect**
**Option A:** *Pyuria (≥10 WBC/hpf)* supports infection.
**Option B:** *Bacterial growth on culture (≥10⁵ CFU/mL)* confirms UTI.
**Option C:** *Nitrites* indicate gram-negative bacteria (e.g., *E. coli*), which reduce nitrate to nitrite.
**Clinical Pearl / High-Yield Fact**
Dysmorphic RBCs in urine always suggest