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Cloacal Prolapse

BASICS

DEFINITION/OVERVIEW

A prolapse is the moving or slipping of a body part from its usual position or anatomic relation. In the reptile, a prolapse from the vent may originate in the cloaca, rectum, phallus, oviduct, or bladder.

ETIOLOGY/PATHOPHYSIOLOGY

The underlying causes for prolapse is often unknown.

See Differential Diagnosis for a list of possible etiologies.

SIGNALMENT/HISTORY

There appear to be no specific signalments or predilections noted for the various reptilian prolapses.

Female reptilians may be overrepresented due to occurrences of dystocia.

CLINICAL PRESENTATION

A prolapse is easy to visualize as abnormal tissue protruding from the cloacal/vent region.

In reptiles housed outdoors and in case of small prolapses, the owners may not notice a problem until days after it has occurred.

A prolapse should be considered as an emergency and evaluated promptly.

The tissue should be kept moist by gently washing the area with water and loosely wrapping in a damp cloth or paper towel until the animal can be evaluated by a veterinarian.

The extruded tissue should be identified to the tissue(s) involved such as cloacal, with/ without bladder, oviduct, proctodeum, colon, phallus, etc.

Once the issues are identified, the clinician may be able to narrow the differential diagnoses (see below) to determine the course of diagnostics and therapeutics.

RISK FACTORS

In cases of nutritional secondary hyperparathyroidism, the muscle tone around the cloacal opening is decreased, leading to potential tissue exposure.

Any generalized physical straining of the patient can lead to tissue exposure through the cloaca, such as dyspnea, obstipation, parasites, infection, etc.

Space‐occupying lesions located in the coelomic cavity, such as uroliths, neoplasia, hepto/renomegaly, eggs, etc., may also cause increase straining and cloacal prolapse.

Husbandry

Several factors of husbandry may lead to one of the clinical conditions listed in the Differential Diagnosis section.

Corrections of the deficient aspects of the husbandry can lead to reversal of some of those listed conditions.

Others

Some cloacal tissue may prolapse during normal oviposition.

Iatrogenic prolapses may occur when owners attempt to manually manipulate ova in suspected cases of dystocia or feces in constipated animals.

DIAGNOSIS

DIFFERENTIAL DIAGNOSIS

Parasites

Hypocalcemia

Dehydration

Metabolic disease

Neoplasia

Impaction

Obstruction

Trauma

Coelomic space occupying lesion

Obesity

Bacterial Infection

Intoxication

DIAGNOSTICS

Radiography and ultrasound may be useful in determining internal abnormalities (e.g., impactions, masses, obstructions).

The small size of some reptiles may lead to reduced imaging detail, which makes interpretation challenging.

Dental radiographs may be a better alternative in smaller species (< 100 g).

A fecal examination should be performed in all cases. This can be directly from the feces, a saline cloacal wash, or direct impression smear of the prolapsed tissue may reveal the presence of parasites such as nematode larvae or eggs.

A CBC and chemistry panel may assist in the determination of underlying physiologic abnormalities.

PATHOLOGICAL FINDINGS

Protozoal infections affecting the gastrointestinal tract may be diagnosed on histopathology.

Other findings will be consistent with the underlying cause but often no specific cause or pathology can be identified.

TREATMENT

APPROPRIATE HEALTH CARE

Treatment often involves direct replacement of the tissue back into normal anatomic position either by manual or

surgical means in combination with correction of the underlying etiology.

The patient should be fully evaluated for general health status and treated accordingly.

The prolapsed tissue should be evaluated for presence of devitalization, which must be surgically or medically addressed prior to prolapse reduction.

In severe oviductal prolapses, discussion with the owner about desired reproductive status should take place with a potential for coeliotomy and ovariosalpingectomy.

In some cases, the internal reproductive structures may be medically or surgically repaired; further reproductive events could result in dystocia.

The prolapse may be reduced in size by coating with a hyperosmotic solution such as 2–5% ophthalmic saline or concentrated sugar solution.

Direct application of dry salt or sugar may be attempted, but the extreme osmolar difference could lead to direct tissue damage and should be closely monitored.

After several minutes of application, the prolapsed tissue should become less edematous and capable of reduction back into the body cavity.

A moistened and lubricated (water soluble) cotton tip applicator or metal probe is used to gently push the tissue back inside the body cavity aligning the lumen.

Surgical options such as resection of the diseased tissue and double‐layer closure can be performed prior to tissue replacement.

In more extensive cases, a coeliotomy/ plastronotomy may be undertaken, with the tissue resection performed within the coelomic cavity where the tissue is in approximate “normal” anatomic position.

Colonic prolapses may require a colopexy where sutures are placed to facilitate the “tacking” of the colon to the dorsolateral body wall.

In cases of reproductive system prolapse (i.e., oviduct), the tissue may be replaced but damage to the suspensory ligaments and internal vasculature may be present.

A purse‐string suture around the cloaca or lateral sutures across the cloacal margin may be placed for 10–14 days to allow for the tissue swelling to resolve in place.

NUTRITIONAL SUPPORT

The reptilian patient may need weight and body condition monitoring to determine whether additional caloric supplementation is needed.

CLIENT EDUCATION/HUSBANDRY RECOMMENDATIONS

If surgical correction of the prolapse was undertaken, the client should be directed on postoperative care of any surgical sites, suture, etc.

A detailed log of activity, as well as food intake/defecations, should be maintained and related back to the veterinarian.

If any changes to the husbandry are determined, the owner should correct those prior to the patient returning home, such as changes to temperature and/or humidity, exposure UVB lighting, etc.

MEDICATIONS

DRUG(S) OF CHOICE

NSAIDs or opioids may be used in management of the inflammation and pain associated with the physical discomfort of the prolapse or surgery.

Depending on the determined etiology, antibiotics or anti‐parasiticides may be indicated.

PRECAUTIONS/INTERACTIONS

When replacing the prolapse, extreme care must be taken not to tear or perforate the delicate, inflamed tissue.

After the sutures are removed, the tissue may re‐prolapse if swelling/inflammation are still present or the underlying etiology has not been corrected.

Placement of additional sutures may be required. Hydration status of the patent must be considered before use of NSAIDs.

FOLLOW‐UP

PATIENT MONITORING

The patient should be followed up daily after clinical repair of the prolapse for reoccurrence.

The owner should monitor and record all food intake and defecations during this time.

Any abnormal changes should be related back to the veterinarian to determine any further changes to the therapy.

EXPECTED COURSE AND PROGNOSIS

Prolapses of the oviduct and bladder tend to have a guarded to grave prognosis due to the degree of underlying physical damage to the affected tissues and cloaca.

Rectal and cloacal prolapses tend to have a fair prognosis if treated promptly.

Phallus prolapses have excellent to good prognosis, as these are purely copulatory organs.

The length of time the prolapse presents has an inverse effect on the prognosis.

When treated early in the disease process and the tissue appears viable, cloacal prolapse replacement may lead to clinical resolution if the underlying etiology is addressed.

Once the tissue begins to desiccate and become devitalized, there is a guarded to grave prognosis.

MISCELLANEOUS

COMMENTS

N/A

ZOONOTIC POTENTIAL

N/A

SYNONYMS

N/A

ABBREVIATIONS

CBC = complete blood count

NSAIDs = nonsteroidal anti‐inflammatory drugs

UVB = ultraviolet B