Neurogenic keratoconjunctivitis sicca in 34 dogs: A case series.

Abstract

OBJECTIVE: To describe the clinical findings, imaging features, underlying conditions, treatment, and progression of dogs presented between 2010 and 2019 with neurogenic keratoconjunctivitis sicca (NKCS). METHODS: Dogs diagnosed with NKCS were searched in the clinical database. Inclusion criteria were STT-1 readings <15&#xa0;mm/min, clinical signs of KCS with concurrent ipsilateral xeromycteria. RESULTS: Thirty-four cases were identified. Mean age at presentation was 8.2&#xa0;years, median 8.9&#xa0;years (0.3-14.7). Twenty dogs were male, and 14 dogs were female. Concurrent neurological deficits included facial neuropathy (n&#xa0;=&#xa0;13, 38%), peripheral vestibular syndrome (n&#xa0;=&#xa0;10, 29%), and Horner's syndrome (n&#xa0;=&#xa0;5, 15%). Advanced imaging was acquired in 53% of cases (n&#xa0;=&#xa0;18). Etiologies included idiopathic (n&#xa0;=&#xa0;18, 53%), endocrinopathy (n&#xa0;=&#xa0;6, 18%), otitis interna (n&#xa0;=&#xa0;4, 12%), head trauma (n&#xa0;=&#xa0;3, 9%), iatrogenic (post-TECA-LBO, n&#xa0;=&#xa0;1, 3%), brainstem mass (n&#xa0;=&#xa0;1, 3%), and an area of inflammation in the pterygopalatine fossa (n&#xa0;=&#xa0;1, 3%). Treatment for NKCS was initiated in most cases (n&#xa0;=&#xa0;30, 88%) including: oral pilocarpine 2% and lacrimostimulant (n&#xa0;=&#xa0;19), oral pilocarpine 2% only (n&#xa0;=&#xa0;3), or lacrimostimulant only (n&#xa0;=&#xa0;8). A mean time follow-up of 3.7&#xa0;months, median 3&#xa0;months (1-14) was available in 23 cases (68%). Eleven cases with follow-up were responsive (48%) with resolution of the clinical signs in a median time 4&#xa0;months (1-10), and all of them were treated with oral pilocarpine (&#xb1;lacrimostimulant). CONCLUSIONS: Most cases presented as idiopathic NKCS; in others, an underlying cause of facial neuropathy was identified. All responsive cases were treated with oral pilocarpine 2%.