# A typical canine Ehlers-Danlos-like syndrome without collagen abnormalities: a suspected case of Tenascin-X deficiency

## TL;DR

A Maltese dog with a fatal Ehlers-Danlos-like syndrome showed unusual elastic fiber issues, possibly due to Tenascin-X deficiency.

## Contribution

This report expands the known spectrum of canine Ehlers-Danlos-like syndrome by identifying a case with elastic fiber abnormalities rather than collagen defects.

## Key findings

- The case presented elastic fiber hypertrophy and fragmentation, not collagen abnormalities.
- The dog exhibited progressive symptoms including skin fragility, joint deformities, and fatal vascular rupture.
- Histopathology suggested a possible Tenascin-X deficiency as the underlying cause.

## Abstract

Ehlers-Danlos syndromes (EDS) are rare heritable connective tissue disorders, most commonly linked to collagen abnormalities. In dogs, reported cases are infrequent and typically involve skin fragility and joint laxity, with limited understanding of underlying genetic causes. This report describes an unusual, aggressive, and fatal case of an Ehlers–Danlos–like syndrome (EDlS) in a Maltese dog, with several uncommon features. Unlike most canine EDS cases, which show collagen defects, this case revealed minimal collagen alterations; instead, elastic fibers were primarily affected.

A one-and-a-half-year-old male Maltese dog presented with progressive abdominal masses, skin fragility, joint deformities, and frequent bruising since early life. Clinical examination revealed hyperextensible, fragile skin, hematomas, and contractures of the hind limbs. Imaging confirmed a hernia lacking supportive connective structures. Histopathological analysis showed elastic fiber hypertrophy and fragmentation, with minimal collagen changes. Despite palliative wound management, the patient died within ten days of the initial consultation due to spontaneous evisceration and vascular rupture.

The histological features are consistent with a possible Tenascin-X deficiency. Definitive molecular classification was beyond the scope of this case. This report expands the spectrum of EDlS in dogs.