Differential Diagnosis for Fecal Incontinence Postpartum
- Single most likely diagnosis
- Anal sphincter injury: The patient's history of a third-degree perineal laceration during delivery, which involves the anal sphincter, is the most likely cause of her fecal incontinence. The weak and asymmetric contraction of the anal sphincter tone supports this diagnosis.
- Other Likely diagnoses
- Pelvic floor dysfunction: The patient's symptoms of fecal and flatal incontinence could also be attributed to pelvic floor dysfunction, which may have been exacerbated by the vaginal delivery.
- Neurogenic causes: Damage to the nerves controlling the anal sphincter during delivery could also lead to fecal incontinence.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Rectovaginal fistula: Although less likely given the intact vaginal walls and lack of abnormal discharge, a rectovaginal fistula could cause fecal incontinence and would require prompt surgical intervention to prevent further complications.
- Infection or abscess: The patient's perineal edema and recent history of laceration repair increase her risk for infection or abscess formation, which could lead to severe consequences if not promptly treated.
- Rare diagnoses
- Congenital conditions: Conditions such as imperforate anus or Hirschsprung's disease are rare and typically present in infancy, but could potentially be diagnosed later in life if symptoms are mild.
- Inflammatory bowel disease: Conditions like Crohn's disease or ulcerative colitis could cause fecal incontinence, but are less likely given the patient's lack of other symptoms such as diarrhea, hematochezia, or weight loss.