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Testing for antinuclear antibodies is the most frequently prescribed analysis for the diagnosis of rheumatic diseases. Indirect immunofluorescence remains the gold standard method for their detection despite the increasing use of alternative techniques. In order to standardize the manual microscopy reading, automated acquisition and interpretation systems have emerged. This publication enables us to present our method of interpretation and characterization of antinuclear antibodies based on a cascade of analyses and to share our everyday experience of the G Sight from Menarini. The positive/negative discrimination on Hep cells 2000 is correct in 85% of the cases. In most of the false negative results, it is a question of aspecific or low titers patterns, but a few cases of SSA speckled patterns of low titers demonstrated a probability index below 8. Regarding the pattern recognition, some types and mixed patterns are not properly recognized. Concerning the probability index correlated in some studies to final titer, the weak fluorescence of certain patterns and the random presence of artifacts that distort the index don't lead us to continue it in our daily practice. In conclusion, automated reading systems facilitate the reporting of results and traceability of patterns but still require the expertise of a laboratory technologist for positive/negative discrimination and for pattern recognition.

A micromethod utilizing paper discs impregnated with different substrates (Minitek-system) permits differentiation of Haemophilus and their biotypes. Differentiation of biotypes presents an assured advantage: it is the only technic for an exact study of non typable H. influenzae strains and NAD-dependent Haemophilus strains. It is also a complement for study of capsulated H. influenzae. In an epidemiological aspect, this differentiation shows a evident predominance of biotypes I and II for H. influenzae and H. para-influenzae. Except that biotype I includes the larger number of serotypable strains, different serotypes are distributed in the five biotypes of H. influenzae. Likewise none relation has been found between biotypes and antibiotypes.