Prolonged Incubation Period for Cryptococcus gattii Infection in Cat, Alaska, USA

Emergence of Clostridium difficile infection due to a new hypervirulent strain, polymerase chain reaction ribotype 078. et al. Multilocus variable-number tandem repeat analysis for investigation of Clostridium difficile transmission in hospitals. To the Editor: We report a case of Cryptococcus gattii infection in a 12-year-old neutered male cat in Alaska. The cat traveled to Anchorage , Alaska (61°N) from San Diego County, California, with its owner in August 2003. Although C. gattii has not been detected in Alaska (where only extremely limited sampling has occurred) or above 49°N (i.e., Van-couver Island, British Columbia), the case suggests that the incubation period for C. gattii could be >8 years. In September 2010, the cat was brought to a veterinary clinic in Anchorage because of facial pruritis and excoriation. The cat did not respond to treatment with methylprednisolone acetate and was referred to a veterinary dermatologist in October. At that time, alopecia, thick scaling, and ex-coriations were observed on ear margins , sides of the head, and between the eyes. The hair coat was sparse, and there was minimal scaling near the tail and lower legs. All foot pads were excessively cross-hatched and scaly. Cytologic analysis of the skin on the head and pinna showed neutrophils and cocci overgrowth. Skin scrapings were negative for mites. Cytologic analysis of the ears did not identify yeast bodies , parasites, or bacteria. A long-acting antimicrobial drug for treatment of skin infections (cefovecin) was given. Biopsy specimens were obtained from the head, ears, and paws, and analysis of these samples supported a diagnosis of mural folliculitis and mild plasma cell pododermatitis. Chest radiograph findings and results of routine blood analysis were not unusual. Test results for feline leukemia virus and feline immunodeficiency virus were negative. Prednisolone (1.8 mg/kg/d) was given; the cat showed a good response and eventual resolution of scaling. Hair grew back but the ste-roid dose could not be reduced to <2.5 mg/d because periodic increases were needed when symptoms flared. In November 2011, the cat was brought back to the veterinary clinic because of worsening of the skin condition even though the owner had increased the prednisolone dose to 7.5 mg/d during the previous 3 weeks. The cat had also started shaking its head frequently and had a unilateral right nasal discharge. Major nasal discharge had not been a symptom previously reported by the owner. Cyto-logic analysis of the discharge showed large yeast bodies …