MKSAP Quiz: Abdominal pain in a type 1 diabetic
This month's quiz asks readers to evaluate a 40-year-old woman in the emergency department for a 7-hour history of gradually worsening generalized abdominal pain, hyperventilation, and lethargy.
A 40-year-old woman is evaluated in the emergency department at 1 a.m. for a 7-hour history of gradually worsening generalized abdominal pain, hyperventilation, and lethargy. Her husband reports difficulty awakening her on several occasions since onset of symptoms, both during the evening and at night. The patient has a 3-day history of nausea and anorexia. She has a 22-year history of type 1 diabetes mellitus treated with insulin. Because she has been unable to eat or drink for the past 3 days, she has reduced her dosage of basal insulin by half and taken no premeal rapid-acting insulin during this period. Her only other medical problem is hypertriglyceridemia. Medications before coming to the emergency department were insulin glargine, prandial insulin glulisine, gemfibrozil, niacin, and daily fish oil.
Physical examination shows a lethargic but arousable woman. Temperature is 96.8 °C (36.0 °F), blood pressure is 105/70 mm Hg, pulse rate is 118/min, and respiration rate is 28/min; BMI is 36. Deep sighing respirations are noted, but the chest is clear to auscultation. She has a sweet smell on her breath. Abdominal examination reveals generalized abdominal tenderness with guarding but no rebound tenderness. Bowel sounds are heard in all four quadrants.
Laboratory studies show hemoglobin 14.7 g/dL (147 g/L), leukocyte count 23,000/µL (23 × 109/L) with 90% polymorphonuclear leukocytes, sodium 149 mEq/L (149 mmol/L), potassium 5.1 mEq/L (5.1 mmol/L), chloride 92 mEq/L (92 mmol/L), bicarbonate 4 mEq/L (4 mmol/L), fasting glucose 615 mg/dL (34.1 mmol/L), amylase 1168 units/L.
Urinalysis shows 4+ glucose, 4+ ketones, no bacteria or leukocytes. A chest radiograph is normal.
Besides administering intravenous fluids and insulin, which of the following is the most appropriate management?
A. Abdominal CT
B. Endoscopic retrograde cholangiopancreatography
C. Imipenem
D. Laparotomy
E. Serial abdominal examinations
MKSAP Answer and Critique
The correct answer is E. Serial abdominal examinations. This item is available to MKSAP 16 subscribers as item 58 in the Endocrinology section. Information about MKSAP 16 is available online.
This patient should first be admitted to the intensive care unit for administration of intravenous fluids and insulin for management of severe diabetic ketoacidosis (DKA) and subsequently have serial abdominal examinations. She has reduced her insulin intake for the past 2 days while she was not feeling well. The insulin requirement usually is increased while a patient is under the stress imposed by illness. Her serum bicarbonate level is now substantially less than 15 mEq/L (15 mmol/L), and she has generalized abdominal pain in the absence of specific intra-abdominal findings on physical examination. These findings are common in DKA, with just under half of patients reporting abdominal pain. Serial abdominal examinations are necessary to determine if her abdominal symptoms improve as her ketoacidosis resolves.
The severity of the abdominal pain is related to the degree of metabolic acidosis. In the absence of localized findings, imaging with CT or other invasive procedures, such as laparotomy or endoscopic retrograde cholangiopancreatography, should be considered only if the patient's abdominal pain does not resolve with correction of the acidosis.
DKA also often causes an elevated leukocyte count, an elevated amylase level, and a less-than-normal temperature, all of which this patient has. However, none of these findings reliably suggests infection, and no obvious source of infection is evident. Imipenem thus should not be started.
Key Point
- Diabetic ketoacidosis can cause generalized abdominal pain, leukocytosis, and hyperamylasemia.