How should I treat an 18‑year‑old woman with type 1 diabetes, severely elevated hemoglobin A1c, hyperglycemia, sulfa‑allergic urinary tract infection with proteinuria, and inadequate carbohydrate‑counting skills while on Lantus (insulin glargine) and Lispro (insulin lispro)?

Management of an 18-Year-Old Woman with Severely Uncontrolled Type 1 Diabetes, UTI, and Inadequate Self-Management Skills

Immediate Priorities: Address the Urinary Tract Infection

Treat the UTI with a non-sulfa antibiotic immediately, as the patient has a documented sulfa allergy. Given the positive leukocytes and nitrites on urinalysis with symptoms of dysuria and frequency, empiric treatment is warranted 1. Appropriate first-line alternatives include nitrofurantoin (100 mg twice daily for 5 days) or a fluoroquinolone such as ciprofloxacin (250 mg twice daily for 3 days) 2. The proteinuria on urinalysis may represent early diabetic nephropathy given the prolonged severe hyperglycemia, but acute infection can also cause transient proteinuria—reassess kidney function and urine protein after treating the infection 1.

Aggressive Insulin Intensification is Mandatory

This patient requires immediate and substantial insulin dose escalation with a structured basal-bolus regimen, as her current doses are profoundly inadequate for an HbA1c of 12.8%. Her total daily insulin dose of 68 units (20 units Lantus + 48 units Lispro) represents approximately 1.0 units/kg/day for her approximate weight, which appears reasonable on paper but is clearly insufficient given her glycemic control 1, 3.

Basal Insulin Adjustment

• Increase Lantus from 20 units to 28-32 units at bedtime immediately (a 40-60% increase), then titrate aggressively by 4 units every 3 days until fasting glucose consistently reaches 80-130 mg/dL 1, 3, 4.
• For an HbA1c > 10% with readings exceeding 300 mg/dL, guidelines support starting doses of 0.5-0.6 units/kg/day total insulin, with approximately 40-50% as basal 1, 3, 4.
• Monitor fasting glucose daily during titration and adjust accordingly 1, 3.

Prandial Insulin Optimization

• The current Lispro dose of 16 units per meal is reasonable as a starting point but requires individualized adjustment based on carbohydrate intake 1.
• Since the patient admits she has "no idea how to measure carbs," the fixed 16-unit dose is essentially functioning as a crude sliding scale rather than true carbohydrate counting 1.
• Increase each meal dose by 2-4 units (to 18-20 units per meal) immediately given the severe hyperglycemia, then teach proper carbohydrate counting to allow flexible dosing 1, 3, 4.
• Administer Lispro 0-15 minutes before meals for optimal postprandial control 1.

Critical Education Intervention: Carbohydrate Counting is Non-Negotiable

Refer this patient urgently to a certified diabetes educator for intensive carbohydrate-counting instruction, as this skill is foundational to type 1 diabetes management. The patient's admission that her relative "did her carb counting" and she has "no idea how to measure carbs" explains much of her deterioration since moving out 1.

• Education should focus on matching prandial insulin to carbohydrate intake (typically 1 unit per 10-15 grams initially), premeal glucose levels, and anticipated activity 1.
• Provide written materials, smartphone apps, and hands-on practice with measuring cups and food labels 1.
• Consider involving a family member or friend who can support her learning process 1.

Establish a Structured Glucose Monitoring Schedule

The patient's current testing frequency of "once every 1-2 weeks" is completely inadequate and must change immediately. For type 1 diabetes on intensive insulin therapy, she should check glucose at minimum 4 times daily: before each meal and at bedtime 1.

• During this period of intensive insulin titration, increase monitoring to 6-8 times daily, including 2-hour postprandial checks 1.
• Strongly consider continuous glucose monitoring (CGM) given her history of poor control and the need for real-time feedback 1.
• CGM can provide alerts for hyperglycemia and hypoglycemia, which is particularly valuable for a young adult living independently 1.

Address the Psychosocial Barriers to Self-Management

This patient's deterioration coincides with her transition to independent living, suggesting significant psychosocial factors beyond simple knowledge deficits. The move from parental home to college represents a high-risk period for young adults with type 1 diabetes 1.

• Screen for depression, anxiety, and diabetes distress using validated tools, as these are common in young adults with poorly controlled diabetes 1.
• Assess for disordered eating behaviors, which are more prevalent in young women with type 1 diabetes and can manifest as insulin omission 1.
• Evaluate her social support network and connect her with peer support groups or online communities for young adults with type 1 diabetes 1.
• Consider referral to a mental health professional with expertise in diabetes if psychosocial barriers are identified 1.

Expected Outcomes and Follow-Up Schedule

With appropriate insulin intensification and education, expect HbA1c reduction of 2-3% over the next 3-6 months (from 12.8% to approximately 9.5-10.8%), with further improvement as carbohydrate-counting skills develop 3, 4, 5.

• Schedule follow-up in 1-2 weeks to review glucose logs, assess UTI resolution, and make further insulin adjustments 3, 4, 5.
• Recheck HbA1c in 3 months to assess response to intensified therapy 1, 5.
• Continue monthly visits until HbA1c falls below 9%, then transition to every 3 months 3, 5.

Common Pitfalls to Avoid in This Clinical Scenario

• Do not delay insulin intensification while waiting for education to "take hold"—the severe hyperglycemia (HbA1c 12.8%, glucose > 300 mg/dL) requires immediate dose escalation to prevent acute and chronic complications 1, 3, 4.
• Do not assume the patient is simply "non-compliant"—her deterioration after moving out suggests she lacks the skills and support system she previously relied upon, not willful neglect 1.
• Do not prescribe SGLT2 inhibitors in type 1 diabetes outside of clinical trials, as they carry significant risk of euglycemic diabetic ketoacidosis and are not FDA-approved for this indication 1.
• Do not continue the current insulin doses unchanged—readings "over 300" with HbA1c 12.8% represent complete therapeutic failure requiring aggressive intervention 3, 4, 5.

Special Consideration: The Proteinuria Finding

The proteinuria on urinalysis warrants further evaluation after UTI treatment is complete. While acute infection can cause transient proteinuria, the prolonged severe hyperglycemia (HbA1c 10.2% four months ago, now 12.8%) places her at risk for early diabetic nephropathy 1.

• Obtain a spot urine albumin-to-creatinine ratio and serum creatinine after completing antibiotic therapy 1.
• If persistent albuminuria is confirmed, initiate an ACE inhibitor or ARB for renoprotection, even in the absence of hypertension 1.
• Screen for other microvascular complications (retinopathy, neuropathy) given the duration and severity of hyperglycemia 1.