Methotrexate (MTX) is indicated for patients with moderate to severe rheumatoid arthritis (RA), but it sometimes causes severe hematologic complications in patients with impaired renal function. We experienced three cases of pancytopenia due to low-dose MTX treatment in RA patients with impaired renal function. Two patients were dialysis patients, and the other had stage 4 chronic kidney disease. The mean cumulative MTX dose and treatment duration for the three patients was 25 mg and 10 days, respectively. All cases experienced severe stomatitis and pancytopenia and recovered with conservative care. In conclusion, MTX should be used cautiously in patients with impaired renal function.
Arthritis, Rheumatoid ; Dialysis ; Humans ; Methotrexate ; Pancytopenia ; Renal Insufficiency, Chronic ; Stomatitis

Pneumocystis carinii pneumonia (PCP), now known as Pneumocystis jirovecii, is a fungal pathogen that causes opportunistic disease, especially pneumonia, in immunocompromised patients. The patients can have a spectrum of illnesses ranging from asymptomatic to fulminant respiratory failure. Here we report two cases with pneumocystis pneumonia after liver transplantation who presented with different clinical features. One patient developed acute respiratory failure requiring mechanical ventilation and expired due to PCP and a superimposed bacterial infection. The other patient was asymptomatic and discovered by regular X-ray check-up. He was successfully treated with trimethoprim/sulfamethoxazole. As shown by our cases, PCP presents with broad clinical manifestations and leads to various clinical courses in liver transplant recipients. Thus, Pneumocystis jirovecii has to be considered a potential pathogen of pneumonia in liver transplant recipients regardless of severity, especially one who is not on prophylactic medications. We consider prophylaxis of PCP in liver transplant recipients in our center.
Bacterial Infections ; Humans ; Immunocompromised Host ; Liver ; Liver Transplantation ; Pneumocystis ; Pneumocystis jirovecii ; Pneumonia ; Pneumonia, Pneumocystis ; Respiration, Artificial ; Respiratory Insufficiency