HISTOLOGICAL AND CYTOLOGICAL SPECIMENS


Histological and Cytological specimens


Histological specimens includes;
Inclusion biopsy
Exclusion biopsy
Curetings
Cytological specimens includes:
Needle aspirates; include fine needle and core needle biopsies
Smears
Washings/lavage
Effusions
Urine
Sputum

Importance of Histological specimens


Both histological and cytological specimens can used for the following purposes-
a.       Diagnosis of diseases: inflammatory conditions, hormonal imbalances, male infertility, chromosome aberrations, micro-organism, pre-malignant conditions and malignant conditions.

b.      Teaching: Gross tissues specimen and stained slides can be used for teaching purposes.
c.       Research: Collected cytological and histological specimens and archived specimens are used in research works.
d.      Forensic: Histological and cytological specimens can be used in determining the cause of death and legal issue e.g. determining a murder, rape cases, paternity dispute.

Histological/Cytological containers


S/No
Specimen
Container
1
Incisional biopsy
Histological  bottle
2
Excisional biopsy
Histological bottle
3
Curretings
Histological bottle
4
Aspirates
Universal bottle
5
Needle biopsy
Universal bottle/Slide*
6
Smears
Slides
7
Washings/lavage
Universal bottle
8
Effusions
Universal bottle
9
Urine
Histological bottle
10
Sputum
Histological bottle
*Slide is not a container but it has been put here to show that as soon as the specimen is collected it had to be smeared/spreaded on slide.

Recommended Specimen-Fixative ratio

Histological specimens
Fixative to be used should be determined before collection of the specimen; will be determined by structures and inclusions to be demonstrated.
Recommended ratio of size of tissue against the volume of fixative should be 1:10.

Cytological specimens
Fluid specimen should never be mixed with fixative prior to smear preparation, instead can be preserved in low temperature i.e. refrigerator temperature. As soon as the smear is prepared. It should be fixed immediately. Prepared smear must be wholly immersed in a fixative used. If spray-fixative is used make sure the whole smear is covered evenly with applied fixative and left to air-dry.

 Key points

·         Histological specimens includes; Inclusion biopsy, Exclusion biopsy and Curretings
·         Cytological specimens includes: Needle aspirates, Smears, Washings/lavage, Effusions, Urine and Sputum
·         Recommend containers for histological and cytological specimens are histological bottles and universal bottle respectively; however smears are prepared on glass slides.

·         To histological specimens, recommended ratio of tissue size against volume of fixative is 1:10. To cytological specimen make sure it is evenly covered or wholly immersed in the fixative used.

Evaluation
·         List any two histopathological specimens
·         Explain any two importances of histological specimens.
·         Mention containers used to histological and cytological specimens.
·         State the recommended ratio of volume of fixative against size of the histological specimen.

                                                                                                                               
References:

·         F.J. Baker, R.E. Silverton, Introduction to Medical Laboratory Technology, 7th Edition, (2001) Oxford University Press;
·         F.I. Carson, Histotechnology, A Self Instructional Text, 3rd edition (2009) ASCP Press
·         R.A.B Drurry, E.A. Wallington, Carleton’s Histological Technique, (1976) Oxford University Press
·         J.D Bancroft, M. Gamble, Theory and Practice of Histological Techniques,6th edition,(2008) Churchill Livingstone Elsevier.

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