Variables significantly associated with raised odds in single variable analysis p< 0.05 (Table 1) but excluded in our multivariable model building (Tables 2 and 3) were chemotherapy, total white cell count, serum C-reactive protein, serum creatinine, serum urea, supplementary oxygen therapy, non-invasive ventilation, Charlson comorbidity index, radiological evidence of pneumonia, chronic lung disease, and peptic ulcer. The gene discussed is CRP; the disease is peptic ulcer disease.