CERTAINTIES AND CONTROVERSIES OF TB DISEASE. DESCRIPTION OF TWO CLINICAL CASES

Introduction and aim. Unspecific clinical presentation of Tuberculosis (TB) and similarity of its signs and symptoms with other diseases make its diagnosis difficult, especially in low burden settings. Early TB diagnosis is extremely important especially when diagnostic delay may result in complications and prolonged treatment as in the patients herein described. Case description. Two cases were enrolled in the Infection Diseases Unit of Ferrara. The first one was a 85 year old Italian man with an history of colic and gastric cancer, surgically treated. In August 2014 he was hospitalized in a Medical Unit for the onset of fever, cough and weight loss. Chest X-ray and CT scan revealed an interstitial pneumonia and a “tree in bud” pattern respectively, diagnosed as “bronchiolitis” and treated with piperacillin/tazobactam and clarithromycin. Two weeks later all symptoms relapsed and the patient was again hospitalized. A chest CT scan showed again the same pattern. A new diagnosis of lung metastases was formulated and a steroid therapy was promptly begun. One week later, owing to a new clinical worsening, the patient was admitted in our Unit, because of unavailability in other wards. On the basis of CT scan, microbiological, citologic and histologic specimens were collected by bronchoscopy and examined. A M. tuberculosis (MTB) PCR performed on brochoalveolar lavage (BAL) resulted positive. The second patient was a 46 year old Moroccan woman suffering from weight loss, fever, cough and night sweats. She also suffered from eosinophilia, epistaxis and dyspnea responsive to bronchodilators. Chest X-ray revealed multiple pulmonary consolidations, confirmed by CT scan which described also a “honeycomb” pattern. MTB search in blood, urine and BAL resulted negative. A “non bacillary TB” was diagnosed and the patient was treated with anti-TB standard regimen. Due to the onset of vision disorders, an opthalmological evaluation and a retinal fluorangiography were required and disclosed a bilateral chorioretinitis which needed discontinuation of ethambutol. While anti-TB treatment was in progress, all the symptoms relapsed. The patient was hospitalized in our Unit, in respiratory isolation precaution. A new chest CT scan showed migrant pulmonary infiltrates with “honeycomb and ground-glass” pattern. IgE dosage was normal. A new bronchoscopy was performed and MTB search was again negative. In the suspect of a Churg-Strauss vasculitis, ANCAs were required and resulted positive. A lung biopsy confirmed this diagnosis. Both patients are now in good physical conditions and symptom-free. The Italian patient has interrupted steroids and started anti-TB therapy, in contrast to the Moroccan woman. Conclusion. TB remains an elusive disease even in countries with advanced medical technology. We underline that difficulties may be encountered in the differential diagnosis due to similar constitutional symptoms and Rx findings peculiar of TB and other non-infectious diseases.