Thursday, December 16, 2010

A New Rapid Test for Detection of HIV

December 13, 2010 | Rochelle P. Walensky, MD, MPH

Published in Journal Watch HIV/AIDS Clinical Care December 13, 2010

Citation(s):

FDA approves bioLytical Laboratories' INSTITM rapid HIV test [press release]. Vancouver, British Columbia, and Chicago, Illinois: bioLytical Laboratories; Dec 1 , 2010. (http://www.biolytical.com/media.html)


The INSTI HIV-1 antibody test delivers results in as little as 60 seconds.

FDA approved INSTI, a new rapid point-of-care HIV-1 antibody test that can provide results from blood and plasma specimens in as little as 60 seconds, with a minimum sensitivity of 99.8% and a minimum specificity of 99.5%. Previously approved rapid HIV tests take 10 to 20 minutes to generate results.

Positive results on any rapid HIV test require confirmation, which usually takes 1 to 2 weeks using standard Western blot or enzyme-linked immunosorbent assay. However, because this new test was generated using different antigens than those used to develop other rapid tests, it opens the door to the possibility of a "rapid/rapid" algorithm, in which one rapid test is used to detect infection and another to confirm it.

Comment:

INSTI offers the unique attribute of faster test processing with nearly immediate delivery of results. Having results within a minute or two alleviates many of the logistical concerns related to patient flow that have challenged clinic-based point-of-care HIV screening programs.

Other tests will probably still have a role, however; the OraQuick rapid HIV test is currently under FDA review for over-the-counter use.

Monday, December 6, 2010

Novel Drugs with Novel Reaction Patterns

Marta R, Philippe-Jean B, Pascal D. Curr Opin Allergy Clin Immunol. 2010;10(5):457-462.

New Risk Factor:

1. Sex

Current studies continue to argue in favor of the female sex as a risk factor for
developing ADRs.

Zopf Y, Rabe C, Neubert A, et al. Gender-based differences in drug
prescription: relation to adverse drug reactions. Pharmacology 2009; 84:333–339.

Macy E, Poon K-YT. Self-reported antibiotic allergy incidence and prevalence: age
and sex effects. Am J Med 2009; 122:778.e1–778.e7.


2. Atopy

May be a risk factor for developing sensitization to beta-lactam antibiotics in
tertiary hospital nurses.

Choi IS, Han ER, Lim SW, et al. Beta lactam antibiotic sensitization and its
relationship to allergic diseases in tertiary hospital nurses. Allergy Asthma
Immunol Res 2010; 2:114–122.



Recent findings Traditional and complementary alternate medicines are also causes of adverse drug reactions, and many of them are cataloged as allergy.

Jacobsson I, Jönsson AK, Gerdén B, et al. Spontaneously reported adverse
reactions in association with complementary and alternative medicine substances in Sweden. Pharmacoepidemiol Drug Saf 2009; 18:1039–1047.


The study showed that 1.2% of the total reports concerned suspected ADRs were related to 175 different CAM products.

The main reactions were urticaria (8.3%), exanthema (7.4%) and contact dermatitis (5.7%).

The most reported were purple coneflower (Echinacea purpurea) (8.1%), Siberian ginseng (Eleutherococcus senticosus), malabar nut (Adhatoda vasica) (7.3%) and ginkgo leaf (Ginkgo biloba) (6.7%).

Zeng ZP, Jiang JG. Analysis of the adverse reactions induced by natural
product- derived drugs. Br J Pharmacol 2010; 159:1374–1391


Three thousand one hundred twenty-two cases involving 140 different drugs were analyzed. Herba houttuyniae and Shuanghuanglian were the most common drugs involved.


Research in the field of skin and drug provocation test to antibiotics such as beta-lactams and carbapenems has allowed the understanding of cross-reactivity reactions and permitted the use of well tolerated alternate drugs in cases of proper negative drug allergy work-up.

Cross-reactions between Imipenem/Cilastatin and Penicillins

Atanasković-Marković M, Gaeta F, Gavrović-Jankulović M, et al. Tolerability of imipenem in children with IgE-mediated hypersensitivity to penicillins. J Allergy Clin Immunol 2009; 124:167–169.

Work on cross-reactivity between penicillins and carbapenems in children with proven IgE-mediated allergy to penicillins.

The rate of cross-reactivity to imipenem/cilastatin detected by skin tests and drug provocation was 0.8%.

Schiavino D, Nuecera E, Lombardo C, et al. Cross-reactivity and tolerability
of imipenem in patients with delayed-type, cell-mediated hypersensitivity to beta-
lactams. Allergy 2009; 64:1644–1648.


Work on cross-reactivity in proven cell-mediated allergy to beta-lactams.

They found a 5.5% rate of cross-reactivity.

These studies open the opportunity to administer imipenem/cilastatin to those patients with proven allergy to penicillins after performing skin tests(immediate and delayed readings) and drug provocation tests.


Many unique cases have been reported, including diverse drugs as infliximab, succinylcholine, hydroxychloroquine, that widen the spectrum of clinical manifestations of drug hypersensitivity to various drugs.


Summary

As new and old drugs continue to be used, new reports regarding new and known drug hypersensitivity manifestations are made. Advances in mechanisms are enhanced by the use of new in-vitro techniques to detect specific antibodies or T cells. Research in the field of skin and provocation tests has allowed the use of well tolerated alternate drugs in individuals with proven drug allergy.