Macter’s Clinical Excellence & Leadership Program (CELP)
Multi Drug Resistant (MDR) tuberculosis, biggest threat to TB control strategies: Experts discussed in the eleventh session of CELP’s National CME Series 2008
KARACHI – “Multi Drug-Resistant (MDR) tuberculosis is a manmade problem which is the biggest threat to our current TB control strategies”, said Dr Muhammad Hussain, Consultant, Department of Pulmonology, Liaquat National Hospital, Karachi, while addressing the 11th Session of the National CME Series, being conducted under the aegis of Clinical Excellence and Leadership Program (CELP) of Macter International.
Dr Hussain elaborated that Multi Drug-Resistant (MDR) tuberculosis may be defined as TB isolate that is resistant to both isoniazid and rifampin; and Extensively Drug-Resistant (XDR) TB as MDR TB with resistance to fluoroquinolone and 1 of the 3 injectable drugs (amikacin, kanamycin, capreomycin).
Discussing about the diagnostic tools available for TB, he termed bacteriology as the simplest, quickest, most reliable and most economical tool. He advised that sputum smear for AFBs should be done for all suspected cases of pulmonary tuberculosis.
Elaborating upon the principles of therapy, he stated that single drug therapy for active TB should not be done and initial intensive phase should be started with at least three or four drugs. He advised that single drug should never be added to a failing regimen. Compliance with therapy remains the major issue, he added.
Dr Zafar Ahmed, Consultant Pulmonologist, in his presentation on asthma stated that asthma is a chronic inflammatory condition of the airways whose cause is only partially known. As a result of inflammation, he explained, the airways become hyper-responsive and they narrow easily in response to a wide range of stimuli. This may result in coughing, wheezing, chest tightness and shortness of breath, he added. Narrowing of the airway is usually reversible but in some patients with chronic asthma the inflammation may lead to irreversible airflow obstruction, said Dr Zafar.
Features of an asthmatic airway caused by chronic inflammation, he explained, include hypertrophied and hyper-plastic smooth muscle, mucosal edema, and increased mucus secretion.
Dr Zafar stated that several factors trigger asthma exacerbations ("attacks") by inducing inflammation or provoking acute bronchoconstriction or both. Inhaled allergens, he informed, such as house dust mite, pollen, animal dander, and spores of fungi are the most common trigger factors, but ingested or injected allergens can also precipitate acute episodes. He explained that pollens usually cause seasonal attacks: tree pollen in spring, grass pollen in summer, and weed pollen in autumn. He further stated that cats and dogs are among the common pets known to trigger asthma attacks due to allergy to their dander, saliva, urine, and feces. Important fungi associated with asthma are Aspergillus fumigatus, which causes episodes generally in late autumn and winter, while among the respiratory infections, rhinovirus is a common culprit, he elaborated. He informed that exercise and associated hyperventilation can exacerbate symptoms through temperature changes of airway mucosa and changes in osmolarity of fluid lining the airway mucosa. Further informing about the trigger factors, he stated that several drugs such as aspirin and other non-steroidal anti-inflammatory drugs, which induce asthma development, can also cause exacerbations, while β-adrenergic blockers provoke bronchoconstriction in asthma patients by blocking β-receptors to endogenous catecholamines. Despite asthma not being a psychosomatic disorder, emotional stress can cause exacerbation indirectly through hyperventilation, he said. Deploring the deteriorating environmental condition, Dr Zafar termed pollution as another important triggering factor for asthma.
Dr Arshad Hussain, Consultant Pulmonologist, in his absorbing presentation on Chronic Obstructive Pulmonary Diseases (COPD) discussed about the disease burden, diagnostic tools and the treatment modalities. He elaborated upon the findings on spirometry and distinguishing features of restrictive and obstructive pulmonary diseases. The last part of his presentation featured case-studies, and the audience actively participated in the discussion.
