Patient Overview
An 81-year-old woman with cervical squamous cell carcinoma (cT2bNXM0, Stage IIB), diagnosed in March 2023, was admitted in January 2024. Her height was 155 cm, weight was 52 kg, and body mass index (BMI) was 21.6 kg/m².
She had no history of hypertension, diabetes mellitus, hepatitis, or tuberculosis. She reported no food or medication allergies. Her medical history included two prior cerebral infarctions without residual neurological deficits. She had undergone cataract surgery ten years earlier with good recovery. She was not taking regular medications before admission.
Radiotherapy for cervical cancer began in April 2023 but was discontinued after seven sessions because of severe lower abdominal pain, increased vaginal bleeding, fatigue, and poor appetite. Between October 11 and November 21, 2023, she completed three cycles of cadonilimab combined with anlotinib. Vaginal bleeding and abdominal pain improved significantly, and repeat computed tomography (CT) showed partial tumor remission. On December 25, 2023, a new cerebral infarction occurred, leading to discontinuation of anlotinib. Cadonilimab monotherapy continued until January 18, 2024.
Clinical Presentation
One week before admission, she developed recurrent abdominal pain. She denied vaginal bleeding, nausea, vomiting, or fever at that time. She was admitted on January 17, 2024, with cervical malignancy and previous cerebral infarction as the initial diagnoses.
Admission vital signs were temperature 36.7 °C, pulse 78 beats/min, respiratory rate 14 breaths/min, and blood pressure 118/76 mmHg. Cardiac, pulmonary, abdominal, and neurological examinations did not reveal significant abnormalities.
Later on the day of admission, she developed frequent nausea, repeated vomiting, and small-volume hematemesis. Initial antiemetic and hemostatic treatment produced limited improvement
Diagnostic Evaluation
Emergency laboratory testing on January 18 demonstrated severe hyperglycemia, with blood glucose exceeding 34.69 mmol/L. A subcutaneous insulin dose of 10 units was administered immediately, but glycemic levels remained uncontrolled. Subsequent evaluation confirmed diabetic ketoacidosis (DKA) with concurrent upper gastrointestinal bleeding.
Key Laboratory Findings:
Date | Parameter | Result | Reference Range |
Jan 18, 2024 | Glucose | >34.69 mmol/L | 4.1-5.9 |
Urea | 11.0 mmol/L | 2.5-6.1 | |
Creatinine | 129.9 μmol/L | 46–92 | |
Blood pH | 7.2 | 7.35-7.45 | |
Carbon dioxide partial pressure | 2.5 kPa | 4.65–5.98 | |
Actual bicarbonate | 7.4 mmol/L | 21-28 | |
Total carbon dioxide | 8.0 mmol/L | 24-32 | |
Base excess | −18.6 mmol/L | −3 to 3 | |
Serum C-peptide | 12.3 pmol/L | 370-1470 | |
Insulin | 32.5 pmol/L | 17.8-173 | |
Urinary ketones | 1+ | Negative | |
Anti-glutamic acid decarboxylase antibody | Negative | 0-10 | |
Anti-insulin antibody | Negative | 0-20 | |
Jan 19, 2024 | Blood pH | 7.34 | 7.35-7.45 |
Glucose | 16.44 mmol/L | 4.1-5.9 | |
Base excess | −5.2 mmol/L | −3 to 3 | |
Jan 22, 2024 | Glucose | 5.8–15.6 mmol/L | 4.1-5.9 |
HbA1c | 6.8% | 4-6 | |
Serum cortisol | 12.41 μg/dL | 8.7-22.4 | |
Adrenocorticotropic hormone (ACTH), 8 am | 3.10 pmol/L | 1.6-13.9 | |
Urinary ketones | 2+ | Negative | |
Blood pH | 7.5 | 7.35-7.45 | |
Actual bicarbonate | 28.9 mmol/L | 21-28 | |
Base excess | 5.5 mmol/L | −3 to 3 |
Management
Following consultation with endocrinology and clinical pharmacy, immune checkpoint inhibitor therapy was discontinued because treatment-related diabetes mellitus was suspected.
Continuous subcutaneous insulin infusion using insulin aspart was initiated at 0.1 U/kg/h. Hourly glucose monitoring guided dose titration. Blood glucose values ranged from 8.5 to 28.1 mmol/L during the first treatment day.
Fluid and electrolyte replacement included 0.9% normal saline, with 1000 mL infused during the first two hours for volume repletion. Serum potassium was closely monitored and supplemented when levels fell below 3.5 mmol/L.
Upper gastrointestinal bleeding was treated with continuous somatostatin infusion until bleeding ceased, after which oral hydration was gradually resumed.
On January 22, insulin therapy was transitioned to multiple daily injections consisting of insulin glargine 10 units at bedtime and insulin aspart 6 units administered 30 minutes before each meal.
Follow-Up
By January 19, metabolic acidosis had significantly improved. Blood pH increased to 7.34, and base excess improved to −5.2 mmol/L. Nausea and vomiting resolved, hematemesis did not recur, somatostatin was discontinued, and oral intake was gradually restarted.
After transition to multiple daily insulin injections, blood glucose remained between 5.8 and 15.6 mmol/L. The onset of immune checkpoint inhibitor-associated type 1 diabetes was documented on January 18, 2024. Long-term insulin therapy was continued because pancreatic beta-cell destruction was considered irreversible and required ongoing insulin replacement.
By January 26, the patient had no recurrence of abdominal pain, vomiting, or gastrointestinal bleeding, and oral intake normalized. She was discharged with diagnoses of cervical malignant tumor (cT2bNXM0, Stage IIB), personal history of cerebral infarction, DKA, and upper gastrointestinal bleeding.
