So far, the tools available to evaluate the nasal involvement and the immunologic status of the patient are the nasal mucosa biopsy, the Mitsuda test, and the ML-flow test.
leprae in the nasal mucosa, in association with methods that determine the specific humoral response against the bacilli, ML-Flow, and the cellular immune response, Mitsuda test, may considerably enhance the accuracy in early diagnosis, treatment decision, and disability prevention.
The Mitsuda test was read by an experienced leprosy specialist 28 days after an intradermal injection of 0.1 ml lepromin suspension (6.0 X 107 bacilli/ml, heat killed, supplied by the Instituto Lauro de Souza Lima, Bauru, Sao Paulo, Brazil) in the upper one-third of the anterior aspect of the right forearm.
One hundred fifty-five (69.8%) of 222 cases were positive in the ML-Flow test, 67 patients (30.2%) were positive in the Mitsuda test, 101 (45.5%) were positive in the nasal biopsy, and 124 (55.8%) were positive in the skin smear.
(6-9) A significant inverse correlation has been shown between the antibody titer and the Mitsuda test, which evaluates the specific cellular immune response against Hansen's bacilli.
A negative correlation was noted between the Mitsuda test results and the BI of the skin smear covering the spectrum of clinical forms.
The cellular immune response was evaluated by the Mitsuda test, which showed an average of 7.4 mm among household contacts.