Differential Diagnosis

The patient's symptoms can be attributed to several possible causes, categorized as follows:

• Single most likely diagnosis

  • B. Clostridium difficile: This is the most likely diagnosis given the patient's recent antibiotic use, which is a well-known risk factor for developing Clostridium difficile infection (CDI). The symptoms of abdominal pain, fever, and watery diarrhea that started after antibiotic administration are consistent with CDI.

• Other Likely diagnoses

  • C. Salmonellosis: Travel to Egypt could expose the patient to various pathogens, including Salmonella. However, the primary symptoms of salmonellosis are typically gastrointestinal, and while it's possible, the recent antibiotic use leans more towards CDI.
  • D. Shigellosis: Similar to salmonellosis, shigellosis could be considered given the travel history and gastrointestinal symptoms. Yet, the context of recent antibiotic use makes CDI more probable.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)

  • A. Antibiotics allergy: Although less likely given the specific symptoms of abdominal pain, fever, and watery diarrhea, an allergic reaction to antibiotics could potentially cause severe and life-threatening reactions. It's crucial to consider this, especially in a patient with a known penicillin allergy, but the symptoms described are more indicative of an infectious process rather than an allergic reaction.

• Rare diagnoses

  • Other rare infectious causes could be considered, but given the information provided, they are less likely. These might include other bacterial, viral, or parasitic infections that could cause similar symptoms but are not as directly linked to the patient's recent travel and antibiotic use as the options listed above.