Diagnostics
literacy.
A Care Partner cannot diagnose. A Care Partner can read the diagnostics the vet has already produced — and translate them for the owner. This module gives you the literacy: a basic blood panel, why SDMA matters more than creatinine, what the Pet-Harmony Score™ actually measures, and where your scope ends.
In this module
The basic panel.
The standard wellness panel for dogs and cats includes the CBC (complete blood count), the chemistry profile, and urinalysis. You will see these results regularly. You should be able to read them at the level of "this is normal, this is flagged, here's what the categories broadly mean" — without ever stepping into interpretation that belongs to the vet.
CBC · the cell-level snapshot
| Marker | What it tracks |
|---|---|
| RBC / HCT / HGB | Red cell capacity. Low = anemia (many causes). High = dehydration or rare conditions. |
| WBC total | Immune activity. High = infection / inflammation / stress. Low = bone marrow issue or overwhelming infection. |
| Neutrophils, lymphocytes, monocytes, eosinophils | The pattern matters more than the totals. Vets read the differential — your job is to flag obvious deviations. |
| Platelets | Clotting capacity. Low = bleeding risk. Very low = emergency. |
Chemistry · organ function
| Marker | What it tracks |
|---|---|
| ALT, ALP, AST, GGT | Liver enzymes. Elevations are common; many causes. Repeat trending matters. |
| BUN, creatinine, SDMA | Kidney function. SDMA is the early warning — see lesson 2. |
| Glucose | Diabetes screen, also stress hyperglycemia in cats. |
| Total protein, albumin, globulin | Nutritional status, hydration, chronic inflammation. |
| Calcium, phosphorus | Many implications — endocrine, kidney, bone, neoplasia. |
| Cholesterol, triglycerides | Endocrine screen, metabolic markers. |
| Total T4 (free T4 if needed) | Thyroid screen. Hyperthyroid in cats >10. Hypothyroid in dogs. |
You don't need to memorize reference ranges. Modern lab reports flag out-of-range values automatically. Your job is to know what each value broadly tracks, so when an owner says "Dr. X said her ALT is high," you can intelligently say "that's a liver marker, and the trend over time matters more than a single value — let's see what Dr. X recommended for the next check."
What screening, when · the AAHA 2023 senior framework
The AAHA 2023 Senior Care Guidelines are the most current, accessible standard for what panels at what age. They define senior as "the last 25% of estimated lifespan" for dogs and ≥10 years for cats. For senior pets, AAHA recommends 1–2× annual workups including CBC, chemistry, urinalysis, plus screening biomarkers SDMA, NT-proBNP, and CRP. Senior pets are now ~44% of the pet population. The toolkit is open-access at aaha.org.
The DISHAA framework for canine cognitive dysfunction
The first formal consensus diagnostic criteria for canine cognitive dysfunction (the dog version of dementia) were published in December 2025 in JAVMA. The clinical screening acronym is DISHAA:
- Disorientation — getting stuck in corners, not recognizing familiar people.
- Interaction changes — withdrawal, irritability, less social engagement.
- Sleep–wake cycle disruption — pacing at night, sleeping all day.
- House-training loss — accidents in previously reliable dogs.
- Activity changes — restlessness, repetitive behaviors, or apathy.
- Anxiety — new fears, separation distress.
Validated screening tools include the CCDR (Cognitive Dysfunction Rating) and CADES (Canine Dementia Scale). When you see two or more DISHAA categories in a senior dog, that's a vet conversation today — early intervention with diet, environmental enrichment and (where appropriate) selegiline meaningfully extends quality of life.
The kidney markers.
Chronic kidney disease is the leading cause of death in cats over 12 and a major cause of senior dog mortality. By the time the historical "go-to" marker — creatinine — rises out of range, the animal has typically lost about 75% of kidney function. SDMA changed that.
SDMA — the early warning
Symmetric dimethylarginine is a methylated arginine excreted almost exclusively by glomerular filtration. It rises with as little as ~25–40% loss of kidney function — vs. creatinine, which only rises after ~75% loss. Crucially, it is not subject to muscle-mass confounding (creatinine drops in cachectic animals, masking decline). The reference interval is 0–14 µg/dL in adult dogs and cats; >14 µg/dL is meaningful; >20 µg/dL suggests advanced disease. For senior cats and at-risk breeds, SDMA on every panel from age 7 is the standard of care in progressive practices.
IRIS staging · how vets categorize CKD
The International Renal Interest Society (IRIS) staging guidelines (2023 update) are how every vet you work with will categorize kidney disease. Stages run 1–4 based on stable, fasted creatinine plus SDMA, with sub-staging by proteinuria (UPC) and blood pressure.
- Stage 1 · no azotemia. The best intervention window. SDMA may be elevated alone.
- Stage 2 · mild azotemia. Many cats live years here with management.
- Stage 3 · moderate. Active treatment territory.
- Stage 4 · severe. End-stage management.
When the vet says "Stage 2 CKD," your translation for the owner is "mild kidney disease, very manageable, here's what changes from now on." The IRIS table is a one-page download from iris-kidney.com — keep it bookmarked.
The four-marker kidney read
- SDMA · early warning. Stage 1 CKD detection.
- Creatinine · later marker. Confirmatory.
- BUN (urea) · less specific. Affected by diet, hydration.
- Urine specific gravity (USG) · concentration ability. Drops early. Often missed without a urine sample.
If your client says "we got blood work, kidneys are fine," the helpful question is: "Did they include SDMA, and did you get a urine sample with USG?" If both answers are yes — great. If one or both are no — gently suggest asking the vet at the next visit. You are not second-guessing the vet. You are advocating for the level of detail that catches decline early.
What about IDEXX vs other labs?
SDMA was developed and is patented by IDEXX. Most Swiss labs run it. Some practices still use older external labs that don't include it as standard — owners can ask. The cost difference is small. The information difference can be 18 months of warning.
"Most chronic decline is invisible until it isn't. SDMA is one of the few places we made it visible earlier."
The Pet-Harmony Score™.
You will be asked about the Pet-Harmony Score by every PETVITY client you work with. Knowing precisely what it is — and equally importantly what it isn't — protects the integrity of the platform and your relationship with the family.
What it is
A composite tracker of healthspan trajectory across four dimensions:
- Body · weight, mobility, energy, sleep, signs of pain.
- Bond · time spent together, training engagement, social environment, household stress.
- Lifestyle · nutrition quality, supplement protocol, environment, daily routine.
- Growth · cognitive engagement, novelty, learning, age-appropriate enrichment.
Each dimension scores 0–25. The composite is 0–100. The score updates as owners complete check-ins (free for all profile holders, weekly for Plus and Premium).
What it isn't
- It is not a diagnosis. It cannot replace a veterinary exam or blood work.
- It is not a clinical biomarker. It uses owner-reported and behavioral data, not blood.
- It is not a guarantee. A high score does not mean a healthy animal — only a well-cared-for one based on the inputs.
- It is not static. A drop matters more than an absolute number. Trend, not point.
How to use it as a Care Partner
The Pet-Harmony Score is a conversation tool. When you visit a client and notice the score has dropped from 78 to 64 over six weeks, the question becomes: "What's changed at home?" That's where your observation skills (Module 3), your nutrition literacy (Module 2), and your foundational vocabulary (Module 1) come together. The score points; you investigate.
When to flag
A sustained Pet-Harmony Score drop of >15 points over 8 weeks, especially in the Body dimension, warrants a recommendation to book the vet. Combine with SDMA / weight / mobility data in your visit log and you've handed the vet a high-signal starting point that saves them and the client time.
Sources & further reading
- IDEXX SDMA · interpretation guide. idexx.com
- IRIS CKD Staging Guidelines (2023) · the international standard. iris-kidney.com
- AAHA 2023 Senior Care Guidelines. aaha.org
- Canine Cognitive Dysfunction · 2025 consensus criteria (DISHAA) · published JAVMA. cvm.ncsu.edu
Module 5 · takeaways
- You read panels at category level. The vet interprets. You translate.
- SDMA catches kidney decline 12–24 months before creatinine.
- The Pet-Harmony Score™ is a tracker, not a diagnostic. Trend > point.
- Body, Bond, Lifestyle, Growth — the four dimensions. 0–25 each. 0–100 composite.
- Drop of >15 points in 8 weeks = recommend vet visit.
Practice question · for your reflection portfolio
A client's 11-year-old cat shows a Pet-Harmony Score drop from 82 to 67 over six weeks, mostly in the Body dimension. The last vet panel was 14 months ago and didn't include SDMA. Write the message you send the owner.
Continue to Module 6 →
Business basics for Care Partners. Pricing your time, insurance, the 35% wholesale, the 10% lifetime referral, building a sustainable practice.
Module 6 · Business → Apply for the cohort