Haw's Syndrome in a Cat: Rapid Response Treatment with 10% Phenylephrine Eye Drops

Abstract

Background: Haw syndrome is an ophthalmological condition characterized by the projection of the third eyelid in cats. Various infectious etiologies have been proposed as potential causes, along with gastrointestinal diseases, endoparasitic alterations, and associations with viral infections. The objective of this study is to report the case of a cat with clinical signs compatible with Haw syndrome, treated on an outpatient basis with serial instillations of 10% phenylephrine eye drops, in three applications every 20 min. This report is important for enhancing the understanding of Haw syndrome in cats and highlighting the effectiveness of treatment with sympathomimetic agents.

Case: A 4-year-and-10-month-old neutered cat mixed-breed, weighing 9.5 kg, was seen with a historical of bilateral 3rd eyelid proptosis, with continuous epiphora and mild local secretion. His owner took him for an ophthalmological evaluation. A history of megacolon, fecal impaction and the need for specific gastrointestinal feeding associated with wet food were reported. Regarding previous ophthalmological history, the owner reported that the pet never had any changes. An ophthalmological evaluation was initiated, and the 3rd eyelid was noted to be prominent in significant intensity, covering almost 60% of the eyeball. Given this history, the owner was informed that a possible diagnosis of HAW Syndrome was required, since the history of changes in the gastrointestinal tract had first appeared and then this bilateral ocular change. Given the situation, it was suggested that compounded eye drops containing 10% phenylephrine be administered in the office to stimulate the sympathetic nervous system and to observe whether there was a response, due to the suspicion of Haw Syndrome, with a history of gastrointestinal alterations on the part of the patient. Instillations were performed at 30-min intervals, and total bilateral regression of the 3rd eyelid was observed. Four topical ocular instillations were performed bilaterally at the same time, observing a total regression of the animal condition. The medication was no longer necessary for application within 15 days under observation. It was suggested that only observation of the ophthalmological condition be performed, since the patient responded positively to the treatment.

Discussion: The Haw Syndrome alteration is increasingly present in the routine clinical ophthalmology of veterinary medicine and its diagnoses. The approach with the best clinical and doctor’s office techniques deserves validation, as treatment options, bringing benefits to patients and tutors, with rapid corrections of the alterations and better quality of life for patients. The faster the diagnosis is made, the greater the chances of reducing the alteration, in addition to the awareness of tutors regarding the incidence of the disease and its association with alterations in the gastrointestinal tract. In addition, it is important to take the patient to the veterinarian as soon as in case of any alteration noticed.

Keywords: eye drops, felines, intestine, eyelid.

Título: Síndrome de Haw em um gato: tratamento com resposta rápida com colírio de fenilefrina a 10%

Descritores: colírio, felinos, intestino, pálpebra.