An 82-year-old woman with dementia and insulin-dependent diabetes mellitus is evaluated at her nursing home due to a urine culture result showing Escherichia coli. Two days ago, the patient was taken to the emergency department due to increased confusion from her baseline that was noted shortly following breakfast. Evaluation revealed mild hypoglycemia and dehydration but normal blood cell counts, serum chemistry studies, chest x-ray, and brain imaging. Urinalysis showed 10-15 leukocytes/hpf and occasional bacteria; a clean catch urine culture specimen was obtained. The patient's confusion resolved with intravenous hydration and normalization of her glucose levels; her medication regimen was reviewed, and she was sent back to the nursing home. A staff member from the emergency department contacts the nursing home as the urine culture grew 100,000 cfu/mL of Escherichia coli sensitive to trimethoprim-sulfamethoxazole and ciprofloxacin. The patient has had no fever, abdominal pain, dysuria, hematuria, or hypoglycemia. Her other medical issues include hypertension, hyperlipidemia, and osteoarthritis. Vital signs are within normal limits. The patient is at her baseline neurocognitive function with orientation to place and person only. Lungs are clear to auscultation and heart sounds are normal. Abdominal examination reveals no suprapubic or flank tenderness. Which of the following is the most appropriate next step in management of this patient's urinary abnormalities?

Question

An 82-year-old woman with dementia and insulin-dependent diabetes mellitus is evaluated at her nursing home due to a urine culture result showing Escherichia coli.  Two days ago, the patient was taken to the emergency department due to increased confusion from her baseline that was noted shortly following breakfast.  Evaluation revealed mild hypoglycemia and dehydration but normal blood cell counts, serum chemistry studies, chest x-ray, and brain imaging.  Urinalysis showed 10-15 leukocytes/hpf and occasional bacteria; a clean catch urine culture specimen was obtained.  The patient's confusion resolved with intravenous hydration and normalization of her glucose levels; her medication regimen was reviewed, and she was sent back to the nursing home.  A staff member from the emergency department contacts the nursing home as the urine culture grew >100,000 cfu/mL of Escherichia coli sensitive to trimethoprim-sulfamethoxazole and ciprofloxacin.  The patient has had no fever, abdominal pain, dysuria, hematuria, or hypoglycemia.  Her other medical issues include hypertension, hyperlipidemia, and osteoarthritis.  Vital signs are within normal limits.  The patient is at her baseline neurocognitive function with orientation to place and person only.  Lungs are clear to auscultation and heart sounds are normal.  Abdominal examination reveals no suprapubic or flank tenderness.  Which of the following is the most appropriate next step in management of this patient's urinary abnormalities?

Quizplus · Accepted Answer

Explanation: This elderly patient with a history of diabetes mellitus and dementia had a transient episode of confusion, possibly due to mild dehydration excerbating hypoglycemia in the setting of insulin use before breakfast. Although her urinary studies were abnormal, including a urine culture result showing Escherichia coli, she has had no manifestations of a urinary tract infection (UTI) such as fever, abdominal pain, hematuria, dysuria, suprapubic/flank tenderness, or continued confusion. As a result, her urinary abnormalities are most likely due to asymptomatic bacteriuria. Asymptomatic bacteriuria is common in women, particularly as they age (prevalence is ~20% in women age >80). Diagnosis is made when a patient with no manifestations of UTI has a clean catch urine culture that reveals >100,000 cfu/mL of a single organism. Some guidelines recommend 2 clean catch urine cultures for diagnosis; however, a second specimen typically confirms the initial result (in >80% of patients). Most cases of asymptomatic bacteriuria are transient and resolve within 2 weeks. Repeat testing or treatment is rarely required; patients can be reassured and observed. Treatment is generally recommended only for those who are pregnant, undergoing urologic procedures, or within 3 months of renal transplantation. (Choice A) Three days of oral trimethoprim-sulfamethoxazole is often used to treat acute, uncomplicated cystitis. This patient has no symptoms of a UTI and does not require antimicrobial treatment. (Choice B) Seven days of oral ciprofloxacin is often used to treat acute pyelonephritis in the outpatient setting. This patient has no manifestations of acute pyelonephritis such as flank pain/tenderness, fever, nausea, and vomiting. (Choices D and E) Even if repeat urine studies showed >100,000 cfu/mL E coli, no treatment would be required in this patient with asymptomatic bacteriuria. If she developed urinary tract symptoms or recurrent confusion, additional testing or treatment could be undertaken. Educational objective: Asymptomatic bacteriuria is common in elderly women. As most cases resolve spontaneously within weeks, no additional testing or treatment is usually required. References: Infectious Diseases Society of America guidelines for the diagnosis and treatment of asymptomatic bacteriuria in adults. (http://www.ncbi.nlm.nih.gov/pubmed/15714408) "Urinary tract infection"-requiem for a heavyweight. (http://www.ncbi.nlm.nih.gov/pubmed/28542707)

An 82-Year-Old Woman with Dementia and Insulin-Dependent Diabetes Mellitus Is