Differential Diagnosis for Sudden Onset of Vomiting, Diarrhea, Petechial Rash, and Temperature at 8 Weeks' Gestation
- Single Most Likely Diagnosis
- Viral gastroenteritis: This is a common cause of sudden onset vomiting and diarrhea, and the presence of a petechial rash could be indicative of a viral etiology such as norovirus or rotavirus. The symptoms presented are consistent with a self-limiting illness.
- Other Likely Diagnoses
- Bacterial gastroenteritis (e.g., Salmonella, E. coli): These pathogens can cause severe gastrointestinal symptoms and could potentially lead to a petechial rash, especially if there is an associated bacteremia.
- Influenza: Although less common, influenza can present with gastrointestinal symptoms, especially in pregnant women, and the petechial rash could be part of a more severe presentation.
- Urinary tract infection (UTI): A UTI can cause systemic symptoms including fever and potentially gastrointestinal upset, though the petechial rash would be less typical.
- Do Not Miss Diagnoses
- Septic abortion or miscarriage: Given the gestational age, any signs of infection or severe illness must prompt consideration of a potential septic abortion or miscarriage, which could be life-threatening.
- Meningococcemia: Although rare, this condition can present with a petechial rash, fever, and potentially gastrointestinal symptoms. It is critical to consider this diagnosis due to its high mortality rate if not promptly treated.
- Listeriosis: This bacterial infection is particularly concerning in pregnancy due to the risk of maternal and fetal complications. It can present with nonspecific symptoms including fever, vomiting, and diarrhea.
- Rare Diagnoses
- Thrombotic thrombocytopenic purpura (TTP): A rare condition characterized by thrombocytopenia, microangiopathic hemolytic anemia, renal failure, and neurological symptoms, which could potentially include a petechial rash.
- Hemolytic uremic syndrome (HUS): Similar to TTP, HUS is a rare condition that could present with a petechial rash among other symptoms, though it is more commonly associated with renal failure and microangiopathic hemolytic anemia.
- Weil's disease (Leptospirosis): A zoonotic infection that can cause a wide range of symptoms including fever, vomiting, diarrhea, and a rash. It is rare but can be severe, especially in pregnant women.