CellaVision Global Test 2026:1 – Infectious Mononucleosis

Case Description

A 19-year-old man was seen in a primary care clinic with a 2-week history of: persistent fatigue, intermittent low-grade fever, mild sore throat, tender posterior cervical lymph nodes, upper left abdominal fullness and reduced appetite.

Laboratory Findings

Complete blood count (CBC):

Test	Result	Reference Interval (male)	Unit
WBC	13.97	4.0 - 10.0	x10⁹/L
RBC	4.57	4.5 – 5.9	x10⁹/L
HGB	13.7	13.5 – 17.5	g/dL
HCT	39.7	41 – 53	%
MCV	86.9	80 - 100	fL
MCH	30.0	27 - 33	pg
MCHC	34.5	32 - 36	g/dL
PLT	116	150 – 400	x10⁹/L
RDW	12.5	11.5 - 14.5	%

Cell Counter Differential:

Test	Result (x10⁹/L)	Unit (%)
Neutrophils	2.26	16.2
Lymphocytes	---	---
Monocytes	---	---
Eosinophils	0.07	0.5
Basophils	0.05	0.4
IG	0.13	0.9
NRBC	0.0	0.0

WBC flags: WBC Abnormal Scattergram, Monocytosis, Blasts/Abnormal Lymphocytes?

Analysis Details

Stain: May–Grünwald–Giemsa

Analyzer: CellaVision DC-1, CDMS 7.2, LED Microscope mode

Sample of cells classified in the Global Test 2026:1

RBC Overview

Case conclusion

Laboratory testing showed a slight leukocytosis (WBC 13.97 ×10⁹/L) and thrombocytopenia (PLT 116 ×10⁹/L). The automated differential was partially unreliable where the lymphocyte population was not reported due to an abnormal scattergram. Analyzer flags indicated abnormal WBC scattergram, monocytosis and possible abnormal/atypical lymphocytes or blasts. Peripheral blood smear examination showed slightly increased WBC count with lymphocytosis with approximately 50% reactive lymphocytes with characteristic dark blue cytoplasm and irregular nuclear shape. Normal hemoglobin and RBC count and a decreased PLT count with PLT clumps present.

Diagnosis

Infectious Mononucleosis

Global Test 2026:1 Results Webinar

Case presentation
DC-1 Analysis - the WBC differential and RBC Characterization
Differences in classification between examiner and participants
Discussion about Mononucleosis – From symptoms to laboratory diagnosis