Presenting Complaints

The patient presents with a 3-day history of watery diarrhea, occurring 5-6 times per day. She reports associated mild abdominal cramping but no fever, nausea, or vomiting.

History of Presenting Complaint

The patient states the diarrhea started 3 days ago, shortly after returning from a 1-week vacation in Spain. She reports eating at several local restaurants during her trip and believes the diarrhea may be related to something she ate. The diarrhea is watery in consistency and she has been passing it 5-6 times per day, with associated mild cramping in the lower abdomen. She denies any blood or mucus in the stool. She has not experienced any fever, nausea, or vomiting. The acute onset of watery diarrhea without fever, nausea, or vomiting, along with the recent travel history, suggests an infectious etiology as the most likely cause.

Significant Positives & Negatives For Differentials

Infectious Gastroenteritis

Positives:

• Recent travel to Spain
• Acute onset of watery diarrhea
• No fever, nausea, or vomiting
• No blood or mucus in stool

Negatives:

• Lack of more severe gastrointestinal symptoms like severe abdominal pain
• No fever

Irritable Bowel Syndrome (IBS) Flare

Positives:

• Patient has a history of IBS
• Diarrhea is a common symptom of IBS

Negatives:

• Acute onset of symptoms rather than chronic/recurrent
• Lack of other typical IBS symptoms like bloating, constipation

Inflammatory Bowel Disease (IBD)

Positives:

• Watery diarrhea can be a symptom of IBD
• No fever, nausea, or vomiting

Negatives:

• Acute onset rather than chronic/recurrent
• Lack of other typical IBD symptoms like abdominal pain, weight loss, blood in stool

Medication-Induced Diarrhea

Positives:

• Patient takes loperamide as needed for IBS
• Diarrhea can be a side effect of some medications

Negatives:

• Acute onset rather than chronic/recurrent
• Lack of other medication-related gastrointestinal symptoms

Past Medical History

The patient has a history of irritable bowel syndrome, for which she takes occasional loperamide as needed. She has no other significant past medical history.

Drug/Medication History

The patient takes loperamide as needed for her irritable bowel syndrome symptoms. She does not take any other regular medications.

Social History

The patient is married and works as an accountant. She lives with her husband in London. She denies any recent sick contacts or travel other than her trip to Spain 3 days ago. She drinks alcohol socially on occasion but does not smoke.

Family History

The patient's family history is noncontributory. Her parents and siblings are all healthy.

Systems Review

• Constitutional: No fever, chills, or unintentional weight loss
• Gastrointestinal: Diarrhea as described, no nausea, vomiting, or abdominal pain
• Genitourinary: No dysuria, hematuria, or change in urinary frequency
• Musculoskeletal: No joint pain or swelling
• Neurological: No headaches, dizziness, or changes in vision

Ideas, Concerns & Expectations

The patient is concerned that she may have contracted a foodborne illness during her recent trip to Spain. She is hoping for treatment to resolve the diarrhea and is worried about missing work due to her symptoms.

Case Presentation

Based on the patient's history and presentation, the most likely diagnosis is infectious gastroenteritis, likely due to a foodborne pathogen contracted during her recent travel to Spain. The acute onset of watery diarrhea without fever, nausea, or vomiting, along with the travel history, strongly points to an infectious etiology. While other diagnoses like IBS flare or IBD are possible, they are less likely given the acute presentation and lack of other characteristic symptoms.