Page 361 - Problem-Based Feline Medicine

18 – THE THIN, INAPPETENT CAT 353

● Histologic evaluation revealing typical pyogranulo- Heart failure, diaphragmatic hernias, neoplasia and
matous is diagnostic. chylothorax may all present signs similar to effusive
FIP in the thorax. Fluid analysis and thoracic radi-
By combining clinical signs with other testing, a high
ographs will help in differentiating the cause of fluid
suspicion of FIP may be obtained.
accumulation.
In the wet form, evaluation of the fluid is helpful.
● Fluid is typically yellow, viscous, and may have
Treatment
fibrin clots.
● Fluid is high in protein (> 35g/L or 3.5 g/dl and usu- Clinical FIP is invariably fatal, and no effective treat-
ally 50–120g/L or 5–12 g/dl) with moderate numbers ment has been found in cats.
of non-degenerate neutrophils and macrophages,
Anti-inflammatory and immunosuppressive ther-
although lower than usual for an exudate.
apy may increase life span by controlling the comple-
● If the albumin:globulin ratio of the fluid is > 0.81,
ment mediated vasculitis, but will not cure the
FIP is an extremely unlikely diagnosis.
condition.
Aspiration of affected organs (liver, lymph nodes, ● Prednisolone (2–4 mg/kg PO daily).
kidney) will often reveal a pyogranulomatous response. ● Cyclophosphamide and chlorambucil may be
used for more potent immunosuppression, but
Increased serum globulin concentration (polyclonal
cytotoxic agents should be avoided in debilitated
gammopathy) is present in the majority of cats with
cats.
FIP.
– Broad-spectrum antibiotic cover should be given
● Other biochemical findings will vary, dependent on
if immunosuppressive drugs are used to prevent
the organ system involved.
secondary infections.
Complete blood count usually often reveals a normo- – Therapy should be re-evaluated regularly,
cytic, normochromic, nonregenerative anemia, a neu- including monitoring for myelosuppression.
trophilic leukocytosis and lymphopenia.
Other immunomodulating drugs (recombinant human
“FIP titers” reported by laboratories are either corona- interferon-α) and anti-viral agents have been promis-
virus titers or titers to the 7B protein in coronavirus. ing in vitro but have limited efficacy in in vivo studies.
Neither are specific for the mutated FIP-coronavirus
Supportive care should be provided if the cat is not
virus. Although claimed that 7B protein was specific
euthanized.
for FIP strains, subsequent studies have shown that it is
not present in some FIP strains, and that non-FIP coro-
navirus may have an active 7B component. Currently
ORAL INFLAMMATORY DISEASE*
there is no serological test that is specific for FIP-coro-
navirus.
Classical signs
● Inappetence associated with dysphagia.
Differential diagnosis
● Weight loss.
FIV, FeLV and toxoplasmosis are the three most com- ● Ptyalism, halitosis and oral pain.
mon differentials for the non-effusive form of FIP. All ● Oral inflammatory, ulcerative and
three can lead to fever, inappetence and weight loss. proliferative lesions.
Toxoplasmosis and FeLV can both present with ocular
and neurological signs. See main references on page 585 for details (The Cat
With Salivation).
Abdominal neoplasia, liver disease (especially cholan-
giohepatitis), pancreatitis, peritonitis and diseases
causing hypoproteinemia can lead to abdominal effu-
Clinical signs
sion. Fluid analysis and cytology of the fluid can fre-
quently distinguish between these diseases. Pure-bred cats may be predisposed.