At baseline, the patient required 4 L of oxygen/minute at rest and 6 L with exertion. Her current home medications included 10 mg of prednisone daily (tapered to 10 mg daily), nintedanib, tacrolimus, mycophenolate, acyclovir, azithromycin, voriconazole, trimethoprim/sulfamethoxazole, metoprolol, atorvastatin, insulin, levothyroxine and gabapentin. A rheumatologist was consulted for severe, worsening and debilitating pain that was refractory to corticosteroid therapy.
On evaluation, the patient reported increased bone pain for the last three months, particularly in her hands, back, arms, legs and shoulders. She denied joint swelling or warmth, but noted that heat packs offered some relief. The pain was described as constant, and she was unable to make a fist or complete her activities of daily living due to severe pain. Her vitals were stable and within normal limits on four liters of oxygen via nasal cannula.
The physical exam revealed diffuse coarse crackles throughout both lung fields, full range of motion in all joints when moved slowly, no evidence of synovitis and diffuse tenderness in the arms, shins, hands, forearms and ribs with moderate pressure palpation. Initial lab results were overall reassuring, with a normal complete blood count (CBC), erythrocyte sedimentation rate (ESR), parathyroid hormone (PTH), 25-hydroxyvitamin D, tacrolimus trough and muscle enzymes. Rheumatoid factor (RF) and cyclic citrullinated peptide (CCP) antibody levels were previously checked and found to be within normal ranges. Aside from an abnormal blood gas (stable from prior), the only other abnormal finding was an elevated alkaline phosphatase (ALP) level at 203 U/L (reference range: 35–105 U/L).
Based on the patient’s history, physical examination, elevated ALP and X-ray findings, voriconazole-induced periostitis (VIP) was diagnosed as the cause of her pain. This diagnosis was further confirmed when her fluoride level returned at greater than four times the upper limit of normal.
