Clinical samples analyzed by microscopy for M. ulcerans.

Table 2 indicates all slides prepared from swab or FNA samples and subjected to Ziehl-Neelsen staining at “Centre Hospitalier Régional” (CHR) for the detection of acid fast bacilli. Slides were analyzed consecutively at CHR and the Department of Infectious Diseases and Tropical Medicine (DITM), Ludwig-Maximilians-University during initial phase (phase I) or CHR, at the “Institut National d'Hygiène” (INH) and DITM during transitional phase (phase II). N/A, not applicable.aMIC, microscopic detection of acid fast bacilli.bTotal, number of slides prepared from swab and FNA samples and subjected to reading at CHR/DITM or CHR/INH/DITM.cPhase I, initial phase of implementation of the national reference laboratory at INH from September 2010 through December 2010; slides were read at CHR and forwarded via DAHWT to DITM for EQA.dPhase II, transitional phase of implementation of the national reference laboratory at INH from January 2011 through April 2012; slides were read at CHR, followed by blinded re-reading at INH and DITM.