Pott's disease and hypercalcemia in a patient with rheumatoid arthritis receiving methotrexate monotherapy
In July 2012, a 74-year-old female patient with a 15-year history of well-controlled RA under MTX monotherapy (10 mg/week) was admitted with a 4-week history of gradually increasing generalized muscle weakness, fatigue, lumbar pain and ulcers on her lips and inguinal region. Her family physician prescribed an analgesic and muscle relaxant for pain relief (phenyramidol hydrochloride 2 × 100 mg/day). At the same time, she was taking treatment for hypertension (telmisartan 80 mg/day) and levothyroxine (100 mg/day) for Hashimoto thyroiditis.\nPatient was referred to medicine department because of the worsening of her complaints and onset of fever. Physical examination of the patient revealed fever (temperature 38.5°C), erosions in the oral mucosa, hemorrhagic crusts on the lower lip and well-demarcated ulcers in the genital region and left medial thigh. Lumbar tenderness, 3/5 muscle weakness and reduced tendon reflexes in both lower extremities were also noted. Laboratory examination revealed pancytopenia along with elevated levels of C-reactive protein (CRP): 15.53 mg/dl (normal: 0-5 mg/dl), aspartate aminotransferase: 120 IU/L (normal: 7-38), alanine aminotransferase: 84 IU/L (normal: 7-35), serum creatinine: 2.01 mg/dl (normal: 0.6-1.2) and blood urea nitrogen (BUN): 53 mg/dl (normal: 8-23). Patient's calcium level was measured as 11.6 mg/dl (normal 8.8-10.2) []. Patient's blood, urine, throat and stool cultures were taken: Owing to the absence, any additional medication or use of contrast substance, pancytopenia and elevated levels of CRP, transferases, BUN and creatinine were attributed to MTX therapy, which was withheld. Serum MTX level was measured higher than the normal therapeutic range. Folic acid treatment was initiated to overcome the toxic effects of MTX. Meropenem (3 g × 1 g intravenous) was started as an empirical initial treatment. Skin biopsy were performed by a Dermatologist revealed papillomatosis in the epidermis and dense eosinophilic infiltration consistent with drug reaction.\nAfter treatment, resolution in the skin and oral lesions was observed. Because of an accompanying hematological disease, bone marrow aspiration and biopsy of the patient were performed and sent for pathological and microbiological evaluation. A normocellular bone marrow with granulomatous foci suggesting megakaryocytosis was reported []. Gram- and acid-resistant staining of the aspirated specimen revealed no bacteria. Due to the patients's lumbar pain, a bone scintigraphy was performed which revealed a pathological involvement in the L4. Further examination with positron emission tomography (PET) (F-18 fluorodeoxyglucose) showed a pathological involvement consistent with inflammation []. A lumbar magnetic resonance imaging (MRI) revealed a psoas abscess causing spinal stenosis consistent with tuberculous spondylodiscitis. A computed tomography (CT)-guided biopsy of the vertebral lesion was performed but no malignancy was reported. Gram- and acid-resistant staining of the vertebral biopsy specimen revealed no bacteria; a culture of this specimen was also obtained. A performed QuantiFERON test was positive. Because all gathered information about the patient was consistent with tuberculosis, tuberculosis treatment was initiated without waiting for the results of the culture specimens. No other additional pathology was found to explain hypercalcemia other than granulomatous foci in the bone marrow and vertebral lesions. Mycobacterium tuberculosis was isolated in cultures of the specimens from the patient's bone marrow and lumbar region. The patient was diagnosed with pancytopenia, renal failure, tuberculous spondylodiscitis and hypercalcemia due to the use of MTX. Anti-tuberculosis therapy yielded an improvement in the patient's clinical status and as well as her hematological and biochemical parameters [].