The recent reports of Burky,1 Thygeson,2 Allen3 and O'Brien and Allen4 indicate an increasing recognition of the important role of toxinproducing staphylococci in conjunctival and corneal inflammations. The common occurrence of saprophytic varieties of staphylococci on the margins of the lids and on the conjunctiva necessitates some test by which toxigenic strains may be recognized readily. Any strain can be tested for its ability to elaborate a conjunctivitis-producing toxin by a method which has been previously described,2 but this is a time-consuming and expensive procedure and not adapted to routine use.
Of the simple tests which have been shown to have some correlation with the production of toxin, the mannitol fermentation test appears to permit of widest application. Overnight readings can be obtained on phenol red—mannitol agar plates inoculated directly from the conjunctiva, a distinct advantage over the coagulase and crystal violet
PHILLIPS THYGESON. MANNITOL FERMENTATION AS AN INDICATOR OF CONJUNCTIVAL PATHOGENICITY OF STAPHYLOCOCCI. Arch Ophthalmol. 1938;20(2):274–275. doi:10.1001/archopht.1938.00850200112005