Vomiting in cats may be clinically relevant even if the owner reports that it occurs only once a month. Also, a lack of vomiting
does not rule out GI disease; cats can compensate for small intestinal disease by absorbing more fecal water in the colon,
resulting in normal-appearing stools. Some cats with GI lymphoma, for example, show only weight loss, with little or no vomiting
or diarrhea. In cats with heartworm disease, a common presenting complaint is chronic vomiting.
Be sure to try to differentiate vomiting from regurgitation, based on the presence or absence of abdominal contractions and
bile or digested blood in the material brought up and on the shape and degree of digestion of the food. Even with a thorough
history, it can be difficult to differentiate vomiting from regurgitation. In these cases, use pH paper to determine the pH
of the material. If it is acidic, the material is of gastric origin and vomiting is confirmed. Regurgitated material tends
to be neutral.
Polyuria and polydipsia
A history of polyuria and polydipsia can indicate many disorders, including hypercalcemia, diabetes mellitus, renal and hepatic
disease, disorders affecting potassium and sodium concentrations, pyometra and other infections, hyperthyroidism, and polycythemia,
as well as with the administration of certain medications (e.g. corticosteroids, diuretics).
Asking about lameness may help you identify diabetic neuropathy, hypertrophic osteopathy, arthropathies, and neoplastic involvement
of bones. Lameness may be the presenting problem in cats with primary pulmonary neoplasia since bronchoalveolar carcinoma
frequently metastasizes to the digits (and tail). If you do not ask about subtle lameness during the history, lameness may
not be identified since cats are often reluctant to walk in the examination room and swelling or increased warmth of joints
may not be detectable on physical examination. A decreased jumping ability may occur in cats with diabetic neuropathy because
of hindlimb weakness and ataxia and vision problems. Diabetic neuropathy may also cause a plantigrade stance.
Neurologic and dermatologic changes
Yawning that is more frequent or is inappropriate for the situation, changes in mentation or behavior, ataxia, or seizures
may be associated with intracranial disease. Cats with hyperthyroidism may show increased activity, increased vocalization,
increased grooming, or an unkempt coat. Pruritus may occasionally result from cholangiohepatitis or other liver disease or
as a paraneoplastic syndrome.2
EXAMINE FROM NOSE TO TAIL
After obtaining a complete history, perform a thorough physical examination in every cat presenting with weight loss. Be sure
to record the cat's weight and body condition score.
Perform a thorough examination of the oral cavity if possible (e.g. if the cat is not resistant, dyspneic, fractious) to detect dental disease, oral masses, stomatitis, gingivitis, or foreign
bodies that may be leading to decreased appetite or dysphagia. Pale mucous membranes could indicate anemia or poor perfusion.
Assess the cat's hydration status by checking capillary refill time, skin turgor, and mucous membrane moistness. Icteric mucous
membranes may be detected in patients with liver or pancreatic disorders or hemolytic anemia. The palate, sclera, pinnae,
and ventral abdomen are good places to check for icterus.
Figure 1. Palpation of submandibular and cervical lymph nodes and thyroid glands can reveal unilateral or bilateral abnormalities.
Palpate all cats older than 6 years for thyroid gland enlargement. Occasionally, the thyroid gland may be cystic, and an enlargement
is not diagnostic for hyperthyroidism. Parathyroid gland enlargement from renal secondary hyperparathyroidism may be mistaken
for thyroid enlargement.
Neoplastic involvement of a lymph node can present with a subtle change in size or firmness of only one lymph node, so carefully
palpate all peripheral lymph nodes (Figure 1), and obtain needle aspirates of any suspicious nodes for cytologic examination. A palpably normal node does not rule out
neoplastic infiltration. Cytology is more sensitive for detecting neoplastic involvement than is palpation and should be performed
whenever lymph node involvement is a concern.