LUPUS VULGARIS OF PINNA: A RARE CASE

Lupus vulgaris is a cutaneous form of tuberculosis that occurs in previously sensitized individuals with a strong positive delayed type of hypersensitivity to tuberculin. Classical lupus lesions are seen in head and neck region and isolated involvement of pinna is rare and therefore high index of suspicion is required for its diagnosis. We present a 39-year-old male with non-healing ulcer of pinna since a year. The diagnosis of lupus vulgaris was conrmed on histopathological evaluation along with positivity for acid fast bacilli. The patient showed well response to standard 4 drug regimen of antitubercular therapy

Fixed drug eruption in the practice of the allergist-immunologist

Fixed drug eruption is a type of allergic reaction to a medicine. The mechanism of this disease is delayed type of hypersensitivity. The spectrum of causative medicines can be variable. A careful history and drug provocation tests in vivo in most cases allow to make a diagnosis accurately and identify the offending drug allergen.

A study of 300 cases of allergic contact dermatitis

<p class="abstract"><strong>Background:</strong> <span lang="EN-IN">Allergic contact dermatitis (ACD) is a delayed type of hypersensitivity from contact with a specific allergen. The aim of the study was to study age, sex incidence of allergic contact dermatitis and incidence of various allergen in patch test positive cases for that allergen in patients presenting to dermatology department in Meenakshi Medical College &amp; Research institute, Kanchipuram.</span></p><p class="abstract"><strong>Methods:</strong> Diagnosis of allergic contact dermatitis was made by patch testing.<strong></strong></p><p class="abstract"><strong>Results:</strong> Most cases of allergic contact dermatitis fall in the age group of 41-50 years. More common in males than females. Allergic contact dermatitis to cement was found to be the commonest cause in our study<span lang="EN-IN">. </span></p><p class="abstract"><strong>Conclusions:</strong> Allergic contact dermatitis is common in middle age and incidence of disease is common in males than females. The higher incidence of allergic contact dermatitis to cement is due to more people being employed in construction working in this part of the world<span lang="EN-IN">.</span></p>

Evaluation of cellular immune response in Golden Hamsters experimentally infected with Leishmania donovani comparing with cellular immune response against chicken Red Blood Cells.

The Evaluation of the immune response in Golden Hamsters experimentally infected with Leishmania donovani was determined in this study, particularly, the cellular immune response. Follow up has maintained to determine the Delayed Type of Hypersensitivity using skin test both in infected and control lab animals. Chicken red blood cells were used as a parameter to evaluate the immune system; they are dull and have the ability of immunization. Two concentrations of chicken R.B.C were examined to determine which gives the higher titration in Hamsters and those were 1.5 X 109 cell/ml and 3 X 109 cell/ml , the second concentration gave the maximum titration where then used in this work. After sensitization with Chicken R.B.C for both infected and control groups, delayed type of hypersensitivity has been used against Leishmania donovani antigen and 4 days of follow up were adopted and they were (14, 30, 60, 90) day after infection. Results showed that skin test against both antigens ( L.donovani and chicken R.B.C) was significantly higher than normal at the first day of follow up ( day 14) then gradual decreasing were noticed till the last day of follow up (90). This can indicate that the infection with L.donovani activated the immune response at the beginning of infection, then leads to cellular immune suppression against both L.donovani antigen and chicken R.B.C., so that this immunosuppression is not specific.

Comparative cellular immune response study of anthraxin prepared by a modified method with antigens extracted from Bacillus anthracis

The study was aimed to comparison of anthraxin prepared by a modifiedmethod from cell-wall extract of avirulent B .anthracis strain 34F2(Sterne)with antigens extracted from the same strain as 1/40 antigen, autoclaved 1/40and the crude toxin. These antigens were compared on their induction of cellmediatedimmunity (CMI) in guinea pigs. Animals were immunized andboosted subcutaneously with the Sterne live veterinary anthrax vaccine. Twoweeks after the booster dose, animals were skin-tested with the four antigens.Anthraxin was the most active antigen which recorded 16.66 mm a mean oferythema and 2.3 mm a difference of skin thickness after 24 hours. Both 1/40and autoclaved 1/40 antigens gave approximately the same results whichwere 12.5 mm as a mean of erythema and 2.25 mm skin thickness for thefirst one; and 12.8mm ,1.66mm for the other respectively. The toxin showedthe lowest results of erythema 7.8 mm with edema. These antigens were alsocompared according to the histological changes on their sites of inoculation.Marked (typical) picture of delayed type of hypersensitivity (DTH) reactionwas occurred for anthraxin

Histoplasmin reaction. Comparison of a polysaccharide antigen to the filtrate antigen

This work was planned by taking into account all the knowledge accumulated from the immunological study of paracoccidioidomycosis. It aimed at comparing a polysaccharide antigen from Histoplasma capsulatum to a classic histoplasmin with the help of intradermal tests of delayed type of hypersensitivity. Tests were applied to 115 individuals in Santo Amaro, a town in the state of São Paulo. Positive results using classic histoplasmin were obtained in 46.0% cases whereas positive results using the polysaccharide antigen at its hightest concentration were obtained in 51.30% cases. The major conclusion in this investigation is that it is possible to use the polysaccharide antigen as histoplasmin instead of the filtrate antigen