Notes from the Field: Tickborne Relapsing Fever Outbreak at an Outdoor Education Camp - Arizona, 2014.

Tickborne relapsing fever (TBRF) is a bacterial infection characterized by recurring episodes of fever, headache, muscle and joint aches, and nausea. In North America, TBRF primarily is caused by Borrelia hermsii spirochetes transmitted by Ornithodoros hermsii ticks. Once infected, these soft ticks are infectious for life and transmit the spirochete to sleeping humans quickly (possibly within 30 seconds) during short feeds (15-90 minutes). On August 10, 2014, the Coconino County Public Health Services District in Arizona was notified by a local hospital that five high school students who attended the same outdoor education camp had been hospitalized with fever, headache, and myalgias. Hantavirus infection initially was suspected because of reported exposure to rodent droppings, but after detecting spirochetes on peripheral blood smears from all five hospitalized students, TBRF was diagnosed. The camp was instructed to close immediately, and the health department, in collaboration with local university experts, investigated to identify additional cases, determine the cause, and prevent further infections. A total of 11 cases (six confirmed and five probable) were identified.

Ocular and systemic findings in a survey of aniridia subjects.

PURPOSE: To determine the prevalence of ocular and systemic abnormalities in a group of subjects with aniridia. METHODS: Survey forms developed by Aniridia Foundation International were sent to all members prior to the 2010 AFI member conference. An additional form was provided for completion by physicians caring for patients. Forms were then collected from all members who attended the meeting. RESULTS: A total of 155 surveys were distributed, of which 83 (53%) were completed. The mean age was 25.4 ± 18.4 years, with 65% sporadic and 35% familial cases, and 2.4% with WAGR (Wilms' tumor, aniridia, genitourinary anomalies, and mental retardation) syndrome. Ocular abnormalities included nystagmus (83%), cataract (71%), dry eye (53%), glaucoma (46%), keratopathy (45%), foveal hypoplasia (41%), strabismus (31%), and retinal disease (5%). The mean age at diagnosis of aniridia was 22.1 months (median, 1.5 months) and glaucoma was 13.6 years (median, 8.5 years). Of 38 subjects with aniridia and glaucoma, 76% were treated medically, and 58% had been treated surgically. In subjects with glaucoma, the mean number (± SD) of glaucoma medications was 1.8 ± 1.3, and number of surgical procedures was 1.7 ± 2.0. Developmental delay was reported in 17%. The mean body mass index and the prevalence of obesity in subjects with aniridia was significantly greater (P = 0.003) than in siblings without aniridia. CONCLUSIONS: In this study, aniridia was associated with nystagmus and other motility problems, cataract, glaucoma, and keratopathy. Systemic abnormalities included increased average body mass index and obesity, which appeared to occur not only in WAGR syndrome but more broadly in aniridia.

Localised retinal vasculitis in cat scratch disease.

We report an atypical presentation of ocular cat scratch disease (CSD) in an 8-year-old Caucasian male who presented with localised retinal arterial vasculitis and associated retinal oedema. His history of headaches, frequent contact with a kitten and a high Bartonella henslelae titre confirmed the diagnosis of CSD. Over an 18-month follow-up period, his best corrected visual acuity in the affected eye improved from 20/30-2 to 20/25+3 without treatment; however, the affected retinal artery remained sheathed.

Impairment of the transient pupillary light reflex in Rpe65(-/-) mice and humans with leber congenital amaurosis.

PURPOSE: To determine the impairment of the transient pupillary light reflex (TPLR) due to severe retinal dysfunction and degeneration in a murine model of Leber congenital amaurosis (LCA) and in patients with the disease. METHODS: Direct TPLR was elicited in anesthetized, dark-adapted Rpe65(-/-) and control mice with full-field light stimuli (0.1 second duration) of increasing intensities (-6.6 to +2.3 log scot-cd. m(-2)). 9-cis-Retinal was administered orally to a subset of Rpe65(-/-) mice, and TPLR was recorded 48 hours after the treatment. TPLR was also measured in a group of patients with LCA. RESULTS: Baseline pupillary diameters in Rpe65(-/-) and control mice were similar. TPLR thresholds of Rpe65(-/-) mice were elevated by 5 log units compared with those of control animals. The waveform of the TPLR in Rpe65(-/-) mice was similar to that evoked by 4.8-log-unit dimmer stimuli in control mice. Treatment of Rpe65(-/-) mice with 9-cis-retinal lowered the TPLR threshold by 2.1 log units. Patients with LCA had baseline pupillary diameters similar to normal, but the TPLR was abnormal, with thresholds elevated by 3 to more than 6 log units. When adjusted to the elevation of TPLR threshold, pupillary constriction kinetics in most patients were similar to those in normal subjects. CONCLUSIONS: Pupillometry was used to quantify visual impairment and to probe transmission of retinal signals to higher nervous centers in a murine model of LCA and in patients with LCA. Mouse results were consistent with a dominant role of image-forming photoreceptors driving the early phase of the TPLR when elicited by short-duration stimuli. The objective and noninvasive nature of the TPLR measurement, and the observed post-treatment change toward normal in the animal model supports the notion that this may be a useful outcome measure in future therapeutic trials of LCA.