CME : Your SA Journal of CPD - Volume 23, Issue 2, 2005
Volume 23, Issue 2, 2005
Source: CME : Your SA Journal of CPD 23, pp 56 –60 (2005)More Less
There are many facets to drug-drug interactions. <BR>Although there are numerous potential drug interactions not all are clinically relevant. <BR>Interactions may either be pharmacokinetic or pharmacodynamic. <BR>Pharmacokinetic drug-drug interactions may occur at any point during absorption, distribution, metabolism or excretion. <BR>Pharmacodynamic interactions may be caused by a large variety of mechanisms making them difficult to study and classify. <BR>Rifampicin, a first-line agent for the treatment of tuberculosis, is a potent liver enzyme inducer. <BR>Most of the drug-drug interactions that occur in patients on TB drug therapy will be due to the enzymeinducing effect of rifampicin. <BR>Isoniazid is an enzyme inhibitor. <BR>When unexpected effects are seen in patients taking many drugs, suspect a drug interaction.
Source: CME : Your SA Journal of CPD 23, pp 62 –66 (2005)More Less
STIs are highly prevalent in South Africa. <br>STIs may cause morbidity and mortality through their impact on reproductive and child health. <br>STIs, particularly those that cause genital ulcers, facilitate the transmission of HIV. <br>STIs have been inadequately managed in the both the public and private health sector of South Africa. <br>The WHO recommends that STIs be managed using the syndromic approach including education, counselling and partner notification. <br>An STI syndrome is identified by a combination of symptoms and signs a patient complains of and it is treated with combination therapy for all the common causes of the syndrome. <br>There are both advantages and disadvantages to managing STIs syndromically but within the South African context, the advantages outweigh the disadvantages.
Management of pulmonary TB in nurse-based Cape Town Metropolitan Local Authority clinics : main topicSource: CME : Your SA Journal of CPD 23, pp 68 –71 (2005)More Less
The South African TB epidemic, enhanced by HIV, poses an increasing challenge. <br>Delayed diagnosis of smear-positive PTB is a major contributor to the spread of TB. <br>Constitutional symptoms and a productive cough exceeding 2 weeks is indication for TB screening. <br>Sputum microscopy remains the main and most cost-effective tool to identify infectious TB. <br>Nurse-based clinics offer free bacteriological screening and treatment of smear-positive PTB. <br>Directly observed treatment (DOT) is a key element in adherence and should apply to every patient on TB treatment. <br>VCT should be offered to all TB patients. Co-infected cases are WHO HIV stage 3 at least, require co-trimoxazole, screening for opportunistic infections, CD4 count and appropriate referral for ARVs.
Author Karin WeyerSource: CME : Your SA Journal of CPD 23, pp 74 –84 (2005)More Less
Multidrug-resistant TB (MDR-TB) is an emerging threat to TB control. <br>Although patient non-adherence is often thought to be the most common cause of drug resistance, many studies have shown that organisational failure of TB control programmes, lack of available drugs, and clinical error are responsible for much of the MDR-TB problem existing today. <br>Although the term MDR-TB has been used to describe resistance to any two or more anti-TB drugs, the correct definition is resistance to at least isoniazid and rifampicin. <br>MDR-TB rates in Africa are among the lowest recorded globally, being ascribed to the late introduction of rifampicin and its limited use in TB control programmes. <br>A recent national survey by the Medical Research Council indicated an overall MDR-TB prevalence of 2.9%, arising from 1.6% of new TB cases and 6.6% of previously treated cases. <br>MDR-TB should be suspected in patients with persistently positive acid-fast bacilli (AFB) smears or cultures despite adequate treatment adherence. <br>Clinical presentation of patients with MDR-TB is identical to that of patients with drug-susceptible disease, and radiological features are indistinguishable. <br>Treatment of MDR-TB involves second-line, reserve drugs that are much more expensive, more toxic and less effective than first-line TB drugs. <br>Design of MDR-TB regimens poses several challenges, complicated by a limited choice of second-line agents. <br>The use of multiple drugs is imperative to avoid amplification of resistance. <br>Treatment must be given under direct observation on at least 5 days a week. Patients must receive a minimum of 16 months' treatment (4 months of intensive and at least 12 months of continuation phase therapy, based on culture conversion) and must complete the full course. Short interruptions of treatment must be corrected by adding the number of drug doses missed. <br>AU MDR-TB patients with HIV co-infection should receive antiretroviral treatment, irrespective of CD4 count.
Source: CME : Your SA Journal of CPD 23, pp 85 –91 (2005)More Less
Sputum smear for AFB remains the cornerstone of TB diagnostics in South Africa. Culture techniques are slow and can be expensive. <br>The HIV epidemic has substantially increased the number of patients with sputum smear-negative TB. Implementing clinical case definitions may allow these patients to be more readily identified and treated.