c.i.-fluorescent-brightening-agent-28 and Acanthamoeba-Keratitis

To compare the efficacy of a battery of routine and special histologic stains for the detection of acanthamoeba keratitis.. Observational study.. Nine patients with culture-proven infectious keratitis whose clinical differential diagnosis included acanthamoeba and who had undergone penetrating keratoplasty were identified. Three cases each of culture-proven acanthamoeba, fungal, and herpes simplex keratitis were reviewed. Serial sections of the keratoplasty specimens were stained with hematoxylin and eosin, periodic acid-Schiff (PAS), Gomori methanamine silver (GMS), giemsa, Gram, calcofluor white, and acridine orange. Sections were reviewed in a random order and a masked fashion and classified as positive or negative for acanthamoeba, fungus, or herpes.. The correct diagnosis was made by examination of the hematoxylin and eosin stained slides in all cases. Correct diagnoses in decreasing order of frequency were made for slides stained with PAS, GMS, acridine orange, calcofluor white, giemsa, and Gram. There were false-positive diagnoses made only with calcofluor white and acridine orange stained slides because of staining of extracellular debris and other material.. When sections are examined by an experienced observer, hematoxylin and eosin is useful compared with calcofluor white, acridine orange, GMS, PAS, giemsa, and Gram stains for the detection of acanthamoeba keratitis.

Topics: Acanthamoeba Keratitis; Acridine Orange; Benzenesulfonates; Cornea; Double-Blind Method; Eosine Yellowish-(YS); Eye Infections, Fungal; False Positive Reactions; Fluorescent Dyes; Hematoxylin; Humans; Keratitis, Herpetic; Keratoplasty, Penetrating; Microscopy, Fluorescence; Predictive Value of Tests; Reproducibility of Results; Staining and Labeling

Corneal infections cause by micro-organisms are the most serious complications of wearing contact lenses. The paper presents the first case of contact lens-associated keratitis caused by the protozoon Acanthamoeba sp. identified in Slovenia so far. The identification of Acanthamoeba as a cause of keratitis in a soft contact lens wearer alerted us to the fact that this health issue should be given more attention in the future.

Topics: Acanthamoeba; Acanthamoeba Keratitis; Adult; Animals; Azure Stains; Benzenesulfonates; Contact Lenses, Hydrophilic; Cornea; Fluorescent Dyes; Gentian Violet; Humans; Male; Microscopy, Fluorescence; Phenazines; Staining and Labeling

The incidence of acanthamoebic keratitis before 1974 is not known. A retrospective study was conducted to understand better the early epidemiology of this infection. Host corneal tissue from therapeutic penetrating keratoplasties submitted to the Stanford Eye Pathology Laboratory from 1955 to 1970 were stained with Calcofluor white and observed by fluorescence microscopy. We reviewed 197 cases, and no misdiagnosed cases of acanthamoebic infection were found.

Topics: Acanthamoeba Keratitis; Benzenesulfonates; California; Fluorescent Dyes; Humans; Incidence; Microscopy, Fluorescence; Retrospective Studies; Staining and Labeling