To explore the early identification, clinical characteristics, diagnosis and treatment, and pregnancy outcomes of pregnancy-related fulminant type 1 diabetes mellitus (FT1DM), in order to improve clinicians' diagnostic and therapeutic approach and increase maternal and fetal survival rates.

A retrospective analysis was conducted on the clinical data of 4 patients with pregnancy-related FT1DM. Additionally, a literature search was performed using the keyword " fulminant type 1 diabetes" in the China National Knowledge Infrastructure (CNKI) and Chinese Journal Full-text Database from January 2000 to December 2024. A total of 222 relevant articles and case reports were retrieved, including 423 patients with FT1DM. Among these, 100 cases of pregnancy-related FT1DM were further screened and analyzed.

All four patients presented with a typical acute onset, rapidly progressing from markedly elevated blood glucose (random blood glucose 18.75-38.69 mmol/L) to diabetic ketosis or ketoacidosis within a short period (1-5 days). They exhibited a " dissociation" phenomenon between extremely high random blood glucose and relatively mildly elevated glycated hemoglobin (6.1%-6.9%), with a PG/HbA1c ratio ≥3.3. Fasting serum C-peptide levels were all <100 pmol/L; pancreatic autoantibodies were negative in 3 patients and not tested in 1. Literature analysis of 100 pregnancy-related FT1DM cases showed that the condition was more common during pregnancy (96%, 96 cases), with acute onset (mean time approximately 3 days). The four patients presented with non-specific prodromal symptoms: gastrointestinal symptoms in 2 cases, respiratory symptoms in 1 case, and neurological symptoms in 1 case.Literature analysis of 100 pregnancy-related FT1DM cases showed that The most common prodromal symptoms were gastrointestinal symptoms (24%, 24 cases), followed by respiratory symptoms (16%, 16 cases). After multidisciplinary treatment, 3 neonates survived and 1 was stillborn. Literature analysis showed that the overall pregnancy outcomes were extremely poor, with a fetal loss rate as high as 60% (mainly stillbirths, accounting for 54%).

Pregnancy-related FT1DM has an acute onset and insidious symptoms, and leads to an extremely high rate of fetal loss. Clinicians should enhance their awareness and remain highly vigilant for any non-specific gastrointestinal or respiratory symptoms in pregnant women without a history of diabetes, considering them as possible prodromal signs of FT1DM. Random blood glucose, urine ketone bodies, and pancreatic function (C-peptide) should be tested immediately, and the key feature of " dissociation between blood glucose and glycated hemoglobin" should be used for early differentiation. Emergency protocols should be initiated, and multidisciplinary collaboration should be implemented to improve maternal and fetal survival.