Page 1201 - Cote clinical veterinary advisor dogs and cats 4th

Lymphangiectasia/Protein-Losing Enteropathy 601

○ Leukocytosis (usually neutrophilic) if ○ Three voided fecal samples are collected ○ Starting dosages should be low (e.g., 5 mL/
underlying inflammatory or infectious into calibrated tubes (available from the kg/day) because acute volume overload
VetBooks.ir • Serum biochemistry profile ○ Primary use is confirming PLE in the shifts of interstitial fluid to the vascular Diseases and Disorders
disease
and pulmonary edema can occur due to
GI Lab, Texas A&M University; http://
www.vetmed.tamu.edu/gilab).
○ Hypoalbuminemia is the hallmark of
compartment.
severe or chronic PLE; serum albumin
presence of coexisting PLN or liver disease.
support and is unlikely to provide useful
concentration may be at the low end of • Rectal scrapings can be examined cyto- ○ Plasma provides modest colloidal
the reference range in the early stages or logically for histoplasmosis or lymphoma amounts of natural anticoagulants such
in patients with effective compensatory (p. 1157). as antithrombin.
responses. • Serum folate and cobalamin concentrations ○ Albumin administration provides only
○ Globulins are often decreased, but this should be measured. temporary improvement in colloidal
finding is variable. ○ Low folate level suggests duodenal disease. status.
○ Hypocholesterolemia is common. ○ Low cobalamin suggests ileal disease, • Electrolyte disorders
○ Hypocalcemia (ionized and total) and exocrine pancreatic insufficiency, or ○ Patients with severe hypocalcemia may
hypomagnesemia are common in patients changes in GI microflora. not improve unless magnesium is also
with lymphangiectasia and reflect reduced • Enzyme-linked immunosorbent assay for His- supplemented.
vitamin D absorption and compromised toplasma antigen can identify histoplasmosis ○ Crystalloids should be administered
parathyroid hormone secretion. (p. 1365). cautiously and used concurrently with
○ Liver enzymes may be slightly elevated ○ False-negative results have been reported colloids to minimize extravascular fluid
with GI disease; differentiate from primary for patients with GI infection. accumulation.
liver disease with serum bile acid testing. ○ Concurrent testing of serum and urine • Abdominal drainage/thoracocentesis (p. 1164)
• Urinalysis may improve sensitivity. ○ Fluid removal is required for patients
○ Rule out proteinuria as cause of • Fecal polymerase chain reaction (PCR) assay with respiratory distress due to cavity
hypoalbuminemia. can confirm infection with H. americana. effusion(s).
○ Hypoalbuminemia due to PLN is generally ○ Test offered by GI Lab, Texas A&M • Total or partial parenteral nutrition provides
associated with a urine protein/creatinine University (http://vetmed.tamu.edu/gilab) interim nutritional support in patients unable
ratio > 5. • GI endoscopy (p. 1098) allows evaluation of to absorb nutrients (p. 1148).
○ PLN and PLE may occur concurrently intestinal mucosa and collection of mucosal
(e.g., soft-coated wheaten terriers) biopsy samples. Chronic Treatment
• Abdominal radiographs ○ General anesthesia is required; this • Effective treatment of PLE requires manage-
○ May be unremarkable or demonstrate loss carries risk for severely hypoalbuminemic ment of the underlying cause; this may not
of serosal detail due to ascites patients. be possible in all patients, particularly those
○ Underlying cause (e.g., mass, foreign body) ○ Samples may be collected from stomach, with intestinal lymphangiectasia.
may be apparent. duodenum, ileum, and colon. • Immunosuppressive agents should be used
• Thoracic radiographs ○ Lesions deeper in intestinal wall may be in patients with idiopathic IBD.
○ May reveal pleural effusion due to missed. ○ Glucocorticoids are the mainstay of
hypoalbuminemia ○ Feeding a small amount of corn oil or medical therapy (e.g., prednisone 1-2 mg/
○ Changes related to underlying cause (e.g., cream 2 hours before induction may kg PO q 12h, tapering to lowest effec-
cardiac, fungal disease) or PTE possible increase visibility of dilated lacteals. tive dose); may not be well tolerated by
• Abdominal ultrasound • Exploratory laparotomy allows visualization severely hypoalbuminemic dogs
○ Ascites may be noted if serum albumin of the entire abdomen and serosal surface of ○ Budesonide 0.5-3 mg/DOG q 24h may be
< 1.5 g/dL. intestine. substituted for prednisone to minimize
○ Intestinal walls may be thickened ± loss ○ Full-thickness biopsies may be diagnosti- iatrogenic hyperadrenocorticism.
of normal layering. cally superior. ○ Additional immunosuppressive agents
○ Hyperechoic mucosal striations suggest ○ Risk of infection or dehiscence, especially (e.g., chlorambucil, cyclosporine, azathi-
lacteal dilation. with hypoalbuminemic state oprine) may be necessary in refractory
○ Focal intestinal lesions may be noted. patients or when chronic therapy is
○ Lymphadenopathy suggests inflammatory, TREATMENT required.
fungal, or neoplastic disease. • Glucocorticoids ± other immunosuppres-
○ Extrahepatic shunt vessels may be noted Treatment Overview sive agents may be helpful in patients with
in patients with portal hypertension. • The long-term goal is to increase serum lymphangiectasia.
• Fluid analysis of ascites or pleural effusion: albumin concentrations. ○ Thought to decrease lipogranuloma forma-
consistent with pure transudate (pp. 1056 • Ultralow-fat diet (<2 g fat/100 kcal) should tion and lymphangitis
and 1343) be provided pending definitive diagnosis. ○ Inflammation triggered by release of
• Fecal evaluation for parasite and pathogen • Some patients need immediate intervention chylomicrons into adjacent tissue exac-
detection to erbates lymphatic dilation, dysfunction,
○ Centrifuged flotation for helminth eggs ○ Mitigate third-space fluid accumulation and leakage.
and protozoal cysts ○ Provide nutritional support • Antibiotic therapy with tylosin (Tylan Soluble,
○ Saline preparation for trophozoites ○ Prevent or address thromboembolic Elanco 20 mg/kg PO q 12h × 4 weeks)
• ± Serum cortisol > 2 mcg/dL (>55 nmol/L) complications may help control intestinal dysbiosis.
excludes hypoadrenocorticism. ○ Address electrolyte imbalances (e.g., • Thromboembolism prophylaxis is warranted
hypocalcemia and hypomagnesemia) (e.g., clopidogrel 1-3 mg/kg PO q 24h)
Advanced or Confirmatory Testing but should be discontinued before surgical
• Canine fecal alpha-1 proteinase inhibitor can Acute General Treatment procedures.
be assayed to confirm PLE. • Colloidal support • Diuretics (spironolactone 1-2 mg/kg PO
○ This protein is similar in size to albumin ○ Synthetic colloids (e.g., hetastarch, q 12h) do not mobilize cavitary effu-
and is resistant to digestion by intestinal dextran) improve oncotic pressure and sions quickly but may delay return of
proteinases. limit peripheral edema and ascites. fluid.

www.ExpertConsult.com