20260805_160838.jpg
What does this cbc suspect in terms of haemoprotozoa ?
Reading File
analyse_media
Finding Sources
Finding Sources
The medical library doesn't cover veterinary haemoprotozoa. I have all the CBC data needed from the image analysis. Let me now provide a thorough analysis.
CBC Analysis - "ALLY" (Dog) - Nihon Kohden Analyzer
Extracted Values
| Parameter | Value | Flag | Reference |
|---|---|---|---|
| WBC | 4.28 × 10³/µL | LOW | 6.0-17.0 |
| RBC | 8.77 × 10⁶/µL | HIGH | 5.5-8.5 |
| HGB | 19.6 g/dL | HIGH | 12-18 |
| HCT | 52.0% | Normal | 37-55 |
| MCV | 59.3 fL | LOW | 60-77 |
| MCH | 22.3 pg | Normal/borderline | 19.5-24.5 |
| MCHC | 37.7 g/dL | HIGH | 31-36 |
| PLT | 0L | CRITICALLY LOW | 200-500 × 10³/µL |
| Granulocytes | 2.71L (63.3%) | LOW abs. | |
| RDW-CV | 13.2% | Normal | |
| RDW-SD | 31.3 fL | Low-normal |
Instrument flags: RBC histogram shows (AT) flag (agglutination), PLT histogram shows (5) flag. WBC shows flags (10) and (11).
Haemoprotozoan Suspicion
This CBC pattern is strongly suggestive of canine babesiosis (Babesia canis / Babesia gibsoni), with secondary consideration for Ehrlichia canis (a rickettsial organism but often grouped with haemotropic pathogens).
Key Diagnostic Clues:
1. Severe Thrombocytopenia (PLT = 0)
This is the single most important finding. Profound thrombocytopenia is the hallmark of:
- Babesia canis - immune-mediated platelet destruction and sequestration
- Ehrlichia canis - bone marrow suppression + immune-mediated destruction
- Anaplasma platys - directly infects platelets (cyclic thrombocytopenia)
2. Elevated RBC / High-Normal HCT with HIGH MCHC
- The RBC count of 8.77 (above ref range) combined with HIGH MCHC (37.7) and the (AT) flag on the RBC histogram is a red flag for RBC agglutination.
- Agglutination causes the analyzer to artificially overcall RBC count and misread MCHC. In reality, the patient may be normocytic or mildly anemic - the machine cannot differentiate agglutinated clumps from individual cells properly.
- Immune-mediated haemolytic anemia (IMHA) secondary to Babesia causes RBC agglutination - this is a classic CBC artifact seen in Babesia infection.
3. Low MCV (59.3 fL) with Low RDW-SD (31.3 fL)
- Microcytosis without high RDW suggests a uniform small cell population - this can be seen with Babesia gibsoni, which preferentially infects smaller, younger RBCs, or may reflect underlying iron-deficiency from chronic haemolysis.
4. Leukopenia / Low Granulocytes
- WBC 4.28 (LOW) with low absolute granulocytes (2.71L)
- Leukopenia + thrombocytopenia = bilineage suppression - classic for Ehrlichia canis (tropical canine pancytopenia), which causes profound bone marrow hypoplasia in chronic phase.
- Also seen in severe acute Babesia.
Most Likely Differential Diagnosis
| Organism | Supports | Against |
|---|---|---|
| Babesia canis / B. gibsoni | Thrombocytopenia, RBC agglutination (AT flag), high MCHC artifact | - |
| Ehrlichia canis | Thrombocytopenia, leukopenia (bilineage), granulocytopenia | Less RBC agglutination |
| Anaplasma platys | Cyclic thrombocytopenia | Less WBC involvement |
| Hepatozoon canis | Possible co-infection (leukocytosis more typical) | WBC is low here, not high |
Primary suspicion: Babesia (likely B. canis or B. gibsoni) based on the combination of:
- Profound thrombocytopenia (PLT = 0 on analyzer)
- RBC agglutination flag (AT)
- Falsely elevated MCHC (agglutination artifact)
- Leukopenia
Co-infection with Ehrlichia canis cannot be excluded and is epidemiologically common (both are tick-borne, often transmitted by Rhipicephalus sanguineus).
Recommended Next Steps
- Blood smear (thin and thick) - look for intraerythrocytic Babesia merozoites (paired piriform "Maltese cross" for B. canis, small ring forms for B. gibsoni)
- Saline agglutination test - confirm or rule out RBC autoagglutination
- PCR for Babesia spp. and Ehrlichia canis - gold standard for speciation
- Serology (IFAT) for Babesia / Ehrlichia
- Repeat PLT by manual count (buffy coat) - automated PLT of zero may be artifactual from platelet clumping, but severe thrombocytopenia is real here
- Check tick exposure history and examine dog for ticks (R. sanguineus)
Note: This is a veterinary CBC (dog). The haemoprotozoa most relevant to canine practice in tick-endemic regions are Babesia canis, Babesia gibsoni, Ehrlichia canis, and Anaplasma platys. The CBC pattern here - particularly the PLT = 0, RBC agglutination flag, and leukopenia - makes tick-borne haemoprotozoan disease (most likely babesiosis) the top differential pending confirmation by blood smear and PCR.
This is a shared conversation. Sign in to Orris to start your own chat.