A 78-year-old man, carpenter, ex-smoker for 22 years, with a history of hypertension, dyslipidaemia and ischaemic heart disease due to acute myocardial infarction that required double coronary bypass surgery. The patient underwent surgery for colon neoplasia with the anatomopathological result of stage III adenocarcinoma (pT3pN2M0). Given the patient's pathological history, the use of fluoropyrimidines is not recommended. For this reason, adjuvant chemotherapy treatment was started according to the TOMOX scheme at adjusted doses (raltitrexed 2.5 mg/m2 and oxaliplatin 100 mg/m2 every 3 weeks). A total of 8 cycles are planned. Tolerance is good. At the follow-up visit prior to the seventh cycle, the patient reported having received antibiotic treatment the previous days for a lower respiratory tract infection diagnosed by his family doctor. He was afebrile, with grade II asthenia and mild deterioration of renal function, so it was decided to postpone the cycle. At that time, the total accumulated doses of raltitrexed and oxaliplatin were 26 mg and 1,040 mg respectively.
Forty-eight hours after this last visit, the patient came to the emergency department with a fever of 38.5oC and dyspnoea on minimal effort. Arterial blood gas analysis showed parameters compatible with severe respiratory failure. Chest X-ray showed bilateral pulmonary infiltrates and dubious condensation in the right lower lobe. The patient was admitted on suspicion of severe pneumonia, and empirical broad-spectrum antibiotic therapy and non-invasive mechanical ventilation were started. Echocardiography ruled out pulmonary thromboembolism. After 48h, due to respiratory worsening, the patient was transferred to the Intensive Care Unit (ICU), requiring endotracheal intubation. The patient was classified as severe respiratory failure secondary to community-acquired pneumonia without isolated germ vs. pulmonary toxicity due to cytostatics associated with adult respiratory distress syndrome. Interactions with the patient's chronic medication were ruled out. The results of microbiological studies (blood and sputum) as well as serology for atypical microorganisms were all negative. Chest CT scan showed a diffuse interstitial pneumonitis component. In view of these results, and given the patient's clinical course, it was decided to initiate high-dose corticosteroid treatment (prednisone 1mg/kg/day), on suspicion of pulmonary toxicity to cytostatics. The patient's evolution was torpid, and he died after 17 days in the ICU.