Differential Diagnosis for 30F with Ongoing Right-Sided Abdominal Pain
Single Most Likely Diagnosis
- Irritable Bowel Syndrome (IBS): Given the chronic nature of the abdominal pain (7 months) and the recent worsening without other alarming symptoms, IBS is a plausible diagnosis. The normal CTKUB and USS abdomen pelvis support this, as they help rule out other structural causes.
Other Likely Diagnoses
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease or ulcerative colitis could present with chronic abdominal pain and could have a variable course, including periods of worsening. The absence of other symptoms like diarrhea, weight loss, or blood in stool does not rule out IBD entirely.
- Functional Dyspepsia: Especially given the treatment for H. pylori, if the symptoms were initially thought to be related to peptic ulcer disease, functional dyspepsia could be a consideration, especially if the pain is related to eating or has a pattern that suggests a relationship with food intake.
- Chronic Appendicitis: Although less common, chronic appendicitis can present with recurrent or persistent right lower quadrant pain without the classic acute appendicitis symptoms.
Do Not Miss Diagnoses
- Ovarian Torsion: Although the USS is normal, ovarian torsion can sometimes not be visualized on ultrasound, especially if it's intermittent. The severe, acute worsening of pain warrants consideration of this diagnosis due to its emergency nature.
- Ectopic Pregnancy: Despite the lack of mention of pregnancy, it's crucial to rule out ectopic pregnancy in any female of childbearing age presenting with abdominal pain, due to its potentially life-threatening nature.
- Appendicitis: Even though the pain has moved from the RUQ to the RLQ and then the rest of the lower abdomen, appendicitis can present atypically, especially in females. The recent worsening of symptoms necessitates considering this diagnosis.
- Intestinal Obstruction: Although less likely given the chronic nature of the symptoms and the normal imaging, an intermittent or partial obstruction could present with variable symptoms and should be considered, especially with worsening pain.
Rare Diagnoses
- Celiac Disease: Could present with chronic abdominal pain, although typically accompanied by other symptoms like diarrhea or weight loss.
- Mesenteric Panniculitis: A rare condition that could cause chronic abdominal pain, usually with a more insidious onset.
- Abdominal Migraine: More common in children but can occur in adults, presenting with recurrent episodes of severe abdominal pain, often without other symptoms.
Each of these diagnoses should be considered in the context of the patient's full clinical picture, including any additional symptoms, physical examination findings, and the results of any further diagnostic tests that may be indicated.