A 41-Year-Old Woman With Back Pain

Robert M. Centor, MD; Christy Collier; Elisa Haley, MD; David McMillion, MD


June 02, 2006

Case Presentation

Ms. A is a 41-year-old white female with a history of chronic back pain and hypertension who presents to the emergency department with the complaint of worsening back pain over the past 3 months. The back pain, which first began 2 years ago, has been diagnosed by her physician as fibromyalgia and has been treated with epidural injections of topiramate (Topamax) and methadone. The pain is constant, 10 on a scale of 1 to 10, and located midline in the thoracic area. No relieving or exacerbating factors have been identified. The severity of the pain has made the patient unable to get out of bed for the past few weeks.

Review of systems reveals that the patient has been amenorrheic for the past 5 months. Surgical history is positive for cholecystectomy at age 31. The patient currently takes duloxetine hydrochloride (Cymbalta) 60 mg/day; methadone 2 mg (2 in the morning, 1 at noon, 2 at bedtime); temazepam (Restoril) 30 mg at bedtime; promethazine (Phenergan) 25 mg every 8 hours as needed; butalbital, acetaminophen, and caffeine (Esgic Plus); topiramate 1200 mg twice/day; propranolol (Inderal) 40 mg twice/day; diazepam (Valium) 5 mg 3 times/day; alprazolam (Xanax) 1 mg 3 times/day; furosemide (Lasix) 40 mg/day; and acetaminophen, aspirin, and caffeine (Goody's Powder), an over-the-counter headache remedy.

Family history is non-contributory. The patient lives with her parents and is currently on disability due to her fibromyalgia. She quit smoking 3 weeks ago due to a loss of taste for cigarettes, but has a 40-pack per year smoking history. She denies alcohol or illicit drug use.

Vital signs on admission were temperature 97.6 F, blood pressure 130/90 mm Hg, pulse 98 beats per minute, respirations 22/minute, and oxygen saturation 96% on room air.

On physical examination, the patient is an obese female with slow, slurred speech. Her oropharynx is dry. Lungs are clear bilaterally. Cardiovascular examination reveals regular rate and rhythm. Her abdomen is diffusely tender to palpation without guarding or rebound tenderness. Extremities are without edema or cyanosis, with 2+ pulses throughout. Neurologic examination shows no abnormalities. Palpation of the patient's spine produced pain that was most pronounced in the thoracic area but no point tenderness or costovertebral angle tenderness.

Laboratory Analyses

The complete blood cell count with differential showed hemoglobin, 15.5 g/dL; hematocrit, 48.2%; platelets, 115 mm3; and total white blood cell count, 16,050/mm3 with 79% granulocytes.

The metabolic profile indicated sodium, 141 mEq/L; potassium, 1.2 mEq/L; chloride, 85 mEq/L; bicarbonate, 46 mEq/L; blood urea nitrogen, 25 mg/dL; creatinine, 0.7 mg/dL; glucose, 147 mg/dL; calcium, 9.0 mg/dL; inorganic phosphorus, 2.3 mg/dL; and magnesium, 1.0 mg/dL.

The arterial blood gas results indicated pH, 7.71; pCO2, 52.9; pO2, 48; and HCO3, (calculated) 65.

The Problem

  • What is the acid-base disturbance?

  • What is the differential diagnosis associated with this acid-base disturbance?

  • What additional studies would you order?


Feel free to discuss this case with others. You can monitor or join in the Medscape discussion at http://www.medscape.com/px/discussions/29d54711.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: