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IPLab:Lab 3:Tuberculosis

Revision as of 22:07, 21 August 2013 by Seung Park (talk | contribs) (Images)

Contents

Clinical SummaryEdit

Two months prior to admission, this 57-year-old white male underwent a routine physical examination. During the course of the examination, a lesion was found in the upper lobe of the right lung. Initially, the patient was treated for two weeks with ampicillin. He was then admitted to the hospital for further study. All studies including sputum studies for tubercle bacilli, bronchial washings, and bronchoscopy were negative and he was discharged.

Upon re-admission, a review of systems revealed the presence of mild dyspnea on exertion, accompanied by a slightly productive cough. Of interest was the fact that the patient had had a positive PPD test for the past 4 to 5 years, but this had never been evaluated. At this time, physical and laboratory examinations were unremarkable. Radiographic examination of the chest revealed a 2 x 2-cm density in the right lower lung field. A CT scan revealed several small cavities in this area.

FindingsEdit

The patient underwent a thoracotomy, at which time a portion of the upper lobe of the right lung was removed. Examination of the cut surface revealed small white nodules measuring up to 0.2 cm in diameter.

ImagesEdit

Study QuestionsEdit


Additional ResourcesEdit

Mycobateria grow very slowly on culture plates, with cultures requiring up to 6 weeks for a positive finding. In lieu of cultures, a more rapid diagnostic test is the PPD--purified protein derivative of tuberculosis--test. PPD is injected under the skin of an individual and then the area is reexamined in 48-72 hours for signs of an inflammatory reaction. A positive test indicates previous exposure to M. tuberculosis.

A thoracotomy is a surgical procedure in which an opening is made in the chest wall.

Nodular hyperplasia of the prostate--characterized by large discrete prostatic nodules--is a common disorder in men over 50 years of age. The nodules cause the prostate to be enlarged and to have an increased weight. The human prostate is surrounded by a restrictive capsule. These nodules cause increased pressure within the capsule which leads to constriction of the urethra as it passes through the prostate. Urethral constriction leads to retention of urine.

A normal PaCO2 is 35 to 45 mmHg.