A 53-year-old woman comes to the urgent care clinic with right-sided abdominal pain that started 2 days ago. She describes the pain as constant, burning, and severe enough to interfere with sleep. There is no associated nausea, vomiting, or diarrhea. The patient tried treating the symptoms with a few doses of over-the-counter antacids and ibuprofen, which brought no relief. Her medical history is significant for breast cancer diagnosed a year ago, for which she underwent a modified radical mastectomy followed by chemotherapy; the last course was completed 3 weeks ago. On physical examination, her temperature is 36.7 C (98 F), blood pressure is 120/70 mm Hg, pulse is 80/min, and respirations are 16/min. Her lung fields are clear to auscultation and her abdomen is soft and nondistended with no rebound, guarding, or rigidity. The liver span is 8 cm and the spleen is not palpable. Bowel sounds are normal. Lightly brushing the skin to the right of the umbilicus elicits intense pain. Which of the following additional features is this patient most likely to develop?
This patient with burning, localized pain and regional hyperesthesia/allodynia, in the context of recent cancer treatment, has common features of herpes zoster (shingles). Pain from shingles may precede the onset of the classic vesicular rash by several days, during which the diagnosis may not be obvious. The possibility of shingles should be considered in patients with regional pain who have no conclusive evidence of disease in the local internal organs.
Shingles may occur at any age, but it is most common after age 50 and the risk increases with age. It is frequently triggered by severe physical stress (such as cancer treatment, as in this patient) or immunosuppressed states, but many cases are spontaneous. Shingles develops when there is reactivation of the varicella zoster virus in a dorsal root ganglion, where it has remained dormant since a past chickenpox infection. This results in pain and a vesicular rash in a dermatomal distribution along the course of the nerve. In some cases, patients may develop persistent hypersensitivity of afferent pain fibers leading to chronic pain known as post-herpetic neuralgia. Treatment with antiviral medications (acyclovir, valacyclovir, or famciclovir) in the first few days of a shingles outbreak can shorten the duration of symptoms and decrease the risk of post-herpetic neuralgia.
(Choice A) Ascites is seen most commonly in patients with advanced liver disease (cirrhosis) or chronic kidney disease. This patient has no liver abnormalities noted in the history or examination findings, and development of ascites would be unexpected.
(Choice B) Black stools (melena) are a typical symptom of upper gastrointestinal hemorrhage (above the ligament of Treitz). Peptic ulcer would be the most likely explanation. Although ibuprofen increases the risk of ulcer, this patient had symptoms prior to taking the medication.
(Choice C) Patients with recent malignancy would be at increased risk for a number of pulmonary conditions, such as pulmonary embolism or pneumonia, which could cause referred pain to the abdomen. However, this patient's abdominal hyperesthesia is not consistent with a pulmonary disorder.
(Choice D) Fever and jaundice in association with right-sided abdominal pain would suggest the possibility of acute cholangitis. Cholangitis is most often associated with biliary obstruction, usually due to gallstones. In the absence of nausea or right upper-quadrant tenderness, biliary obstruction is less likely.
(Choice E) Patients with impending bowel perforation, as in acute appendicitis, often develop initial symptoms in the periumbilical area. Abdominal examination should yield more specific clues to this possibility, and hyperesthesia would be unlikely.
(Choice F) Small-bowel obstruction is a common cause of abdominal pain, but it most often occurs in patients with adhesions from prior abdominal surgery. It is usually associated with nausea and abnormal bowel sounds.
Educational objective:
Herpes zoster (shingles) is due to reactivation of varicella zoster virus from a dorsal root ganglion. Patients experience pain and a vesicular rash in a dermatomal distribution. The pain may precede the rash by several days, during which the diagnosis may not be apparent.