Differential Diagnosis for the 10-year-old Chow Chow

The following differential diagnosis is organized into categories to help prioritize potential causes of the symptoms presented.

• Single most likely diagnosis

  • Canine Cognitive Dysfunction (CCD): This condition is similar to Alzheimer's disease in humans and is common in older dogs. Symptoms such as barking at nothing, staring, pacing, and changes in sleep patterns align with CCD. The age of the dog and the combination of behavioral changes and physical symptoms like stiffness support this diagnosis.

• Other Likely diagnoses

  • Hypothyroidism: This hormonal disorder can cause a variety of symptoms including skin issues, weight gain, and stiffness, which could explain some of the dog's symptoms. The lump on the neck could potentially be related to a thyroid gland issue.
  • Cushing's Disease: This condition, caused by an overproduction of cortisol, can lead to symptoms such as increased urination, vomiting, and changes in behavior. The dog's age and some of the physical symptoms could suggest Cushing's Disease.
  • Sensory Decline: The dog's poor vision for treats at her feet and stiffness could indicate sensory decline, which is common in older dogs and can contribute to accidents in the house and changes in behavior.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)

  • Diabetes Mellitus: Although less likely given the absence of polydipsia (excessive thirst) and polyphagia (excessive hunger) in the description, diabetes can cause increased urination and accidents in the house. It's crucial to rule out diabetes due to its significant impact on the dog's quality of life and the need for prompt treatment.
  • Kidney Disease: Chronic kidney disease can cause vomiting, increased urination, and other symptoms mentioned. Given the dog's age and the presence of small pee accidents, kidney disease is a critical differential diagnosis that should not be missed.
  • Cancer: The lump on the neck could be a sign of cancer, which would require immediate attention. Various types of cancer can cause a range of symptoms, including those described.

• Rare diagnoses

  • Neurological Disorders (e.g., seizures, neuropathies): While less common, neurological disorders could explain some of the dog's behavioral changes and physical symptoms. Conditions affecting the brain or nerves could lead to a variety of symptoms, including barking at nothing, OCD behavior, and changes in vision or hearing.
  • Inflammatory or Infectious Diseases: Certain inflammatory or infectious diseases affecting the brain, kidneys, or other organs could potentially cause the dog's symptoms. These would be less common but should be considered if other diagnoses are ruled out.