Exacerbation of tracheobronchitis due to nontoxigenic Corynebacterium diphtheriae.

A 54-year-old womanwas admitted to our hospital on February 7, 1 994, with persistent productive cough, sore throat, and bloody sputum. She had realized an exacerbation of cough and mucopurulent sputum about 2 months prior to admission and had had bloody sputum on January 3 1. The patient had been in her usual state of health, with productive cough and postnasal drip for a few years; she had thought her symptomswere typical usual and thus she never visited a doctor. The physical examination on admission revealed her to be almost normal. Posterior rhinoscopy revealed mucopurulent postnasal drip and nasal polyps. The laboratory data on admission were as follows. White blood cell count was 3,200/jnl; erythrocyte sedimentation rate, 28 mm/hr; CRP 0.2 mg/dl. Serum IgG 2433 mg/dl, IgA 735 mg/dl, IgM 195 mg/dl, IgE 197 mg/dl, and cold hemagglutination xl28 were determined. The CPK level was 37 IU// and the electrocardiogram was normal. Chest X-ray revealed no significant findings. Bronchoscopy on admission revealed diffuse tracheobronchitis and grayish fibrinous exudate over the tracheal mucosa fromjust below the vocal cord to the first carina (Fig. 1). It was very thick and blocked the lumen of the airway. It was difficult to remove by suction and the biopsy specimens revealed no bronchial neoplasm. Based on these findings we tentatively diagnosed this case as tracheal tuberculosis ( 1 ) complicated with chronic sinobronchitis, which we call sinobronchial syndrome (SBS) (2) in Japan. The patient began taking oral erythromycin (EM) 600 mg a day (low dose, long-term erythromycin therapy) (3, 4) for SBS and lg cephazolin sodium (CEZ) intravenously every 12 hours only for 2 days for prophylaxis of iatrogenic infection following bronchoscopy. From the smear of sputum and bronchial lavage fluid we detected gram-positive rods and Klebsiella ozaenae but did not detect Mycobacterial species. After 3 days of oral erythromycin therapy, she recovered from severe illness and on day 5 of hospitalization her complaints were almost completely relieved. On day 7 follow-up bronchoscopy revealed only mild tracheobronchitis, no grayish exudate, and no stenotic lesions. On the same day, the gram-positive rods cultured from bronchial lavage fluid obtained on admission were proven to be Corynebacterium diphtheriae (mitis). Biological characteristics of the bacteria were as follows: glucose (+), maltose (+), sucrose weakly (+), lactose (-), mannitol (-), xylose (-), urease (-), nitrate reduction (-),