ISSUE25

ISSUEMay
2022

This issue
Last Month’s Slides P.1
Monthly Digital Case study P.1-2
Cell Quiz P.2
Malaria P2-3

Last Month’sSlides
Slide 1
Patient hospitalised inclinical haematology.
Follow-up of amyeloproliferative
syndrome
Hyperleukocytosis.
Myelemia. Basocytosis.
Erythroblastosis. Anaemia.
Thrombocytopenia. To becompared with the rest of
the clinical assessment.
Expert's comment: Aspectof MPS (Myelofibrosis?)Monthly Digital Case Study
May 2022 Slide 3
Presentation
59-year-old Female

Slide 2Control of white blood celldifferential. Anisocytosis(++) RDWsd (62fL).
Dacryocytes (+). Discrete
myelemia. Discrete
basocytosis.
Thrombocytopenia.
Presence of macroplatelets.

Slide 3

FBC Results
WBC 2.0* (10^3/mm3)
RBC 2.31*(10^6/mm3)
HGB 6.5*(g/dL)
HCT 20.8* (%)
MCV 90(fL)
MCH 28.1 (pg)
MCHC 31.1(g/dL)
PLT
160 *10^3/mm3)

RBC with HowellJolly Body

Target Cell

Erythroblast

Abnormal Neutrophil

See Case Study on the right

Slide 4
Some Granular
Lymphocytes

Slide 5Population of lymphocyteswith often irregular nuclei
and sometimes granularcytoplasm

Slide 6Nothing abnormal detected

Slide review
Leukopenia with erythroblastosis.
Result of white blood cells with aflag by the analyser++ Hypochromasia+++ RBC Target Cells+ Howell Jolly Bodies
27% Erythroblasts
Corrected WBC = 1.5 (10^3/mm3)
Abnormal Neutrophils

Cell Quiz:
An elderly patient presentswith extensive red rash(erythroderma), enlarged
spleen and lymph nodes.
Blood film shows numbersof abnormal lymphocytes
like the one above. Whatcondition may be present?

Malaria - Part 2
Testing for Malaria
The diagnosis of malaria is confirmed by blood tests which areeither microscopic or non-microscopic tests.
The microscopic tests involve staining and direct visualisation of the parasite
under the microscope. The direct microscopic visualisation of the parasite on
the thick and/or thin blood smears has been the accepted method for thediagnosis of malaria in most settings, from the clinical laboratory to the fieldsurveys, for over a hundred years. Careful examination of a well-prepared andwell-stained blood film currently remains the “gold standard” for malaria
diagnosis.

Microscopic Testsa) Glandular Feverb) Sezary Syndromec) Allergic reaction

High quality thick and thin films should be prepared and examined in every
suspected case ofmalaria, regardless of the results ofimmunochromatographic rapid diagnostic tests (RDTs) for malarial antigen
detection.
A thick film should be used to detect presence of malaria parasites and the thinfilm for identification of species. It is useful to prepare four thick films and fourthin films so that two of each can be stained, leaving spare films to send to areference centre and for further study if there is diagnostic difficulty. Films
should be made as soon as possible to avoid morphological alteration ofparasites which occurs with storage of K2EDTA-anticoagulated blood. After
collection of the blood sample, the film is stained with Romanowski stains toexamine the intracellular appearance of the red cells.

Last Month’s Cell
Quiz:
What can be seen in the redcell?

Thin FilmThin smears allow one to identify malaria species (including the diagnosis ofmixed infections), quantify parasitaemia, and assess for the presence ofschizonts, gametocytes, and malarial pigment in neutrophils and monocytes.
Thin blood films stained by Giemsa’s or Leishman’s stain are useful for
specification of parasites and for the stippling of infected red cells. The optimal
pH of the stain is 7.2.

Thick Film

Answer:The cell image shows
Basophilic Stippling

The thick smear of correct thickness is the one through which newsprint isbarely visible. It is dried for 30 minutes and not fixed with methanol. Thisallows the red blood cells to be haemolysed and leukocytes and any malaria
parasites present will be the only detectable elements. However, due to thehaemolysis and slow drying, the plasmodia morphology can get distorted,making differentiation of species difficult. Thick smears are therefore used todetect infection, and to estimate parasite concentration.

Differential of Malaria Parasites

QSP 2.0

Thick films are usually stained by the rapid Field’s technique or Giemsa’s stainfor screening of parasites. The sensitivity of a thick blood film is 5-10
parasites/µl.

Available as a single use
license and a site license
which allows up to 50
concurrent users.
To find out more, contact
us.

Rapid Testing Kits (RTD’s)
Malaria rapid diagnostic tests (RDTs) supplement the diagnosis of malaria byproviding evidence of the presence of malaria parasites in blood. RDTs are aused in addition to microscopy, particularly where good quality microscopy
experience is not available. The test works by detecting specific antigens(proteins) produced by malaria parasites in the blood of infected individuals.
It is a lateral flow immuno-chromatographic antigen-detection tests, whichworks by capturing dye-labelled antibodies to produce a visible band on a stripof nitro-cellulose in a cassette casing. With malaria RDTs, the dye-labelled
antibody first binds to a parasite antigen, and the resultant complex iscaptured on the strip by a band of bound antibody, forming a visible line (T test line) in the results window. A control line (C- control line) gives
information on the integrity of the antibody-dye conjugate, but does notconfirm the ability to detect parasite antigen. Some kits can only detect one
species (Plasmodium falciparum or P. vivax) while others detect multiple
species (P. falciparum, P. vivax, P. malariae and P. ovale).

Bibliography
https://www.ncbi.nlm.nih.gov/books/NBK555962/(Bain, 2006; Bain et al, 2011)https://www.who.int/teams/gl
obal-malaria-programme
Essential Haematology
A.V .Hoffbrand & J.E.Pettit
Moody AH, Chiodini PL.
Methods for the detection ofblood parasites. Clin Lab
Haematol 2000;22:189-201.

Editorial Team
Kelly Duffy
Andrew Fisher

About us
Other Tests
Some laboratories use quantitative buffy coat (QBC) on positive samples,
however this is an expensive method.

PCR is another method, which is very sensitive and reliable when determining
the species of malaria in a mixed infection. This is mainly used in referencelabs.
For all positive cases of malaria, it is required to send 1 EDTA blood sample onwhich the film was made, together with 2-3 blood films from the same
sample, to a Malaria Reference laboratory.

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