Case study: Pain with no obvious source
Ms. P, 65 years old, presented to our family practice clinic for evaluation of right lower quadrant (RLQ) and right flank pain. A constant vague pain had been escalating in intensity over the past five days and was now described as severe and stabbing in nature. Pain was neither alleviated nor aggravated by OTC analgesics, rest, or movement. There were no intolerances to food. No fever, chills, nausea, vomiting, constipation, or diarrhea was reported. Ms. P had not experienced any recent changes in bowel patterns and had no urinary frequency, burning, or urgency. There was no known recent injury.
Past medical history
The patient was well known to our clinic, having multiple conditions, including hypothyroidism, hypertension, hyperlipidemia, coronary artery disease, migraine headaches, and musculoskeletal complaints. She had recently had a negative breast biopsy after a suspicious mammogram. There was no history of diverticular disease, inflammatory bowel disease, or irritable bowel syndrome. The only abdominal surgery was a hysterectomy and oophorectomy 20 years ago.
Vital signs were stable. Temperature was 98.4ºF, pulse 64 beats per minute, respiration rate 16 breaths per minute, BP 128/60 mm Hg, height 6 ft, and weight 153 lb. The initial examination was unremarkable except that Ms. P exhibited marked guarding when the RLQ was palpated. Rebound tenderness was negative as were psoas, obturator, and Murphy's signs. No masses were palpated, and there was no organomegaly. The patient demonstrated no costovertebral angle tenderness. Urine dipstick was within normal limits, and urine culture was later determined to be negative. Ms. P's initial diagnosis was unspecified RLQ abdominal pain.
We sent Ms. P for an abdominal and pelvic CT with IV contrast dye. Imaging revealed no pathologic enhancement of the appendix or periappendiceal inflammation. No hydronephrosis or hydroureter was evident on either side. No renal or ureteral calculi were visualized bilaterally. The spleen was unremarkable.
The liver, gallbladder, adrenal glands, and pancreas showed no gross abnormalities. There was no lymphadenopathy. No bowel obstruction, free air, or fluid was visualized. The patient's uterus was surgically absent. Lung bases were clear. Any need for surgery was ruled out, and the source of pain could not be determined by CT.
At the emergency department
Herpes zoster (HZ) was not considered as a differential diagnosis until Ms. P sought medical care at a local emergency department 11 days after the initial episode of pain. Ms. P noticed the eruption of a rash in the affected area. She was treated with an antiviral agent and a narcotic and sent home with instructions to follow up with her primary-care provider.
Fifteen days after initial onset of pain, the patient returned to the clinic reporting continued discomfort. A 5- × 6-cm clustered vesicular rash was evident on the right lateral flank area, along with a 2- × 3-cm cluster on the right hip. All lesions were along the T11 dermatome.
Many of the vesicles had already crusted over and appeared to be healing. Interestingly, no vesicles appeared on the abdomen where her pain had been reported to be most intense at the first visit. The skin over the RLQ was still tender to palpation. The remainder of the exam was otherwise within normal limits. She was instructed to finish the antiviral regimen and given prescriptions for an opioid analgesic and a tricyclic antidepressant to decrease her pain.