Congenital cranial ventral abdominal hernia, peritoneopericardial diaphragmatic hernia and sternal cleft in a 4-year-old multiparous pregnant queen

True Diaphragmatic Hernia (Morgagni Hernia) Incidentally Diagnosed with Positive Contrast Peritoneography in a Cat: A Rare Case Report and a Review

An 18-month-old neutered male domestic shorthair cat was presented for an emergency consultation after falling from the second floor. The cat sustained minor traumatic injuries but did not exhibit dyspnea. Routine radiographic examination raised suspicion of a diaphragmatic hernia, but the circumscribed nature of the soft tissues visible in the thorax was atypical for a classic traumatic diaphragmatic hernia. A positive contrast peritoneography highlighted the likely presence of a hernial sac, which strongly suggested a "true diaphragmatic hernia", also known as "pleuroperitoneal hernia". This diagnosis was confirmed during laparotomy, which allowed for the visualization of a 3 cm radial diaphragmatic defect in the right ventral quadrant of the pars sternalis. The diaphragm's edges were rounded. A portion of the falciform ligament and a part of the omentum were protruding through the defect and were contained within a hernial sac. Herniorrhaphy was performed. The cat recovered without complications. Given its presentation and location, ventrally and to the right, this anomaly is analogous to what is described in humans as "Morgagni hernia". Six other cases of Morgagni hernias have probably been reported in cats but were not identified as such. This case underscores the utility of peritoneography, a straightforward technique useful for diagnosing diaphragmatic hernias, which enables differentiation between acquired traumatic forms and congenital forms, particularly peritoneopericardial hernias and pleuroperitoneal hernias. True diaphragmatic hernias are almost always serendipitous discoveries.

Congenital peritoneopericardial diaphragmatic hernia in a family of Persian cats

Case series summary

The congenital midline defects of peritoneopericardial diaphragmatic hernia (PPDH) and omphalocele are believed to be related developmental defects, and have both been described in cats and dogs. This case series describes multiple cases of PPDH and omphalocele in related cats. The majority of cats affected with midline defects (PPDH or omphalocele) were male, consistent with previous reports of male overrepresentation.

Relevance and novel information

This is the first report of a family of Persian cats affected by PPDH and/or omphalocele. Clinical findings and pedigree information are suggestive of an autosomal recessive mode of inheritance. However, other modes of inheritance cannot be ruled out owing to limited sample size. The findings in this family and previous reports of Persians affected by PPDH warrant further investigation. Based on this information, recommendations for breeding populations of Persians and long-haired cats should include thoracic radiographs to screen for PPDH until a DNA-based genetic test is available.