Lower urinary tract infection: Clinical sciences

Lower urinary tract infections, or lower UTIs, primarily include infections of the urinary bladder and urethra, called cystitis and urethritis respectively. Most UTIs are caused by bacteria that typically compose the normal gastrointestinal flora, especially gram-negative rods, such as E. coli, followed by Klebsiella pneumoniae and Proteus mirabilis. Depending on the setting and patient’s risk factors, lower UTIs can be classified as uncomplicated, complicated, CAUTI, and UTI in pregnancy.

Alright, if a patient presents with signs and symptoms suggestive of a lower UTI, you should first perform an ABCDE assessment to determine if they are unstable or stable. If unstable, first stabilize the airway, breathing, and circulation. This means you might have to intubate the patient, provide supplemental oxygen, obtain IV access, and monitor vital signs before doing further workup.

Now that you know how to manage unstable patients, let’s go back to the ABCDE assessment and discuss stable ones. If your patient is stable, you should first perform a focused history and physical examination, and order labs like a urinalysis and urine culture. History might reveal symptoms like dysuria, urinary frequency and urgency, and sometimes even blood in urine. On the other hand, physical exam could reveal suprapubic tenderness to palpation. As far as labs go, the urinalysis will be positive for nitrites and leukocyte esterase, and will reveal pyuria or WBCs and possibly hematuria or RBCs.

Now here’s a clinical pearl to keep in mind! It’s important to note whether hematuria is painful or painless. Painful hematuria suggests diagnoses like infection or nephrolithiasis. On the other hand, painless hematuria can be a sign of underlying conditions such as renal malignancies, polycystic kidney disease, or autoimmune rheumatologic conditions, such as IgA nephropathy. At this point, you should suspect a lower UTI.