T cell deficiency

{{Infobox medical condition (new)

| name = T cell deficiency

| synonyms =

| image = Healthy Human T Cell.jpg

| alt =

| caption = Human T Cell

| pronounce =

| field = Immunology

| symptoms = Eczematous

| complications =

| onset =

| duration =

| types = Primary or Secondary

| causes =

| risks =

| diagnosis = Delayed hypersensitivity skin test, T cell count

| differential =

| prevention =

| treatment = Bone marrow transplant, Immunoglobulin replacement

| medication =

| prognosis =

| frequency =

| deaths =

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T cell deficiency is a deficiency of T cells, caused by decreased function of individual T cells, it causes an immunodeficiency of cell-mediated immunity. T cells normal function is to help with the human body's immunity, they are one of the two primary types of lymphocytes (the other being B cells).{{medical citation needed|date=May 2017}}

Symptoms and signs

Presentations differ among causes, but T cell insufficiency generally manifests as unusually severe common viral infections (respiratory syncytial virus, rotavirus), diarrhea, and eczematous or erythrodermatous rashes. Failure to thrive and cachexia are later signs of a T-cell deficiency.

Mechanism

In terms of the normal mechanism of T cell we find that it is a type of white blood cell that has an important role in immunity, and is made from thymocytes.Alberts B, Johnson A, Lewis J, Raff M, Roberts k, Walter P (2002) [https://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=mboc4&part=A4422 Molecular Biology of the Cell] {{Webarchive|url=https://web.archive.org/web/20101112203832/http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=mboc4 |date=2010-11-12 }}. Garland Science: New York, NY pg 1367 One sees in the partial disorder of T cells that happen due to cell signaling defects, are usually caused by hypomorphic gene defects.{{Cite journal |last=Cole |first=Theresa S. |last2=Cant |first2=Andrew J. |date=2010 |title=Clinical experience in T cell deficient patients |journal=Allergy, Asthma & Clinical Immunology |volume=6 |issue=1 |pages=9 |doi=10.1186/1710-1492-6-9 |issn=1710-1492 |pmc=2877019 |pmid=20465788 |doi-access=free}} Generally, (micro)deletion of 22Q11.2 is the most often seen.{{Cite book |last=Prasad |first=Paritosh |url=https://books.google.com/books?id=DbptoZipfKkC&q=T+cell+deficiency++epidemiology&pg=PT124 |title=Pocket Pediatrics: The Massachusetts General Hospital for Children Handbook of Pediatrics |date=2013 |publisher=Lippincott Williams & Wilkins |isbn=9781469830094 |page=Google books gives no page |language=en |access-date=19 May 2017 |archive-url=https://web.archive.org/web/20220407103335/https://books.google.com/books?id=DbptoZipfKkC&q=T%20cell%20deficiency%20%20epidemiology&pg=PT124 |archive-date=7 April 2022 |url-status=live}}

= Pathogens of concern =

The main pathogens of concern in T cell deficiencies are intracellular pathogens, including Herpes simplex virus, Mycobacterium and Listeria.[https://books.google.com/books?id=iPuvQDcqW88C&pg=PA435 Page 435] {{Webarchive|url=https://web.archive.org/web/20230112210459/https://books.google.com/books?id=iPuvQDcqW88C&pg=PA435 |date=2023-01-12 }} in: {{Cite book |last=Jones, Jane |title=Infection: Microbiology and Management |last2=Bannister, Barbara A. |last3=Gillespie, Stephen H. |publisher=Wiley-Blackwell |year=2006 |isbn=978-1-4051-2665-6}} Also, intracellular fungal infections are also more common and severe in T cell deficiencies. Other intracellular pathogens of major concern in T cell deficiency are:

{{columns-list|colwidth=30em|

Mycobacterium avium intracellulare
Salmonella species
Rhodococcus equi
Pneumocystis jirovecii
Toxoplasma gondii
Cryptosporidium parvum
Leishmania species
Herpesviridae (herpes simplex, cytomegalovirus and varicella zoster)
Cryptococcus neoformans
Histoplasma capsulatum

}}

Diagnosis

The diagnosis of T cell deficiency can be ascertained in those individuals with this condition via the following:{{Cite web |title=T-cell count: MedlinePlus Medical Encyclopedia |url=https://medlineplus.gov/ency/article/003516.htm |url-status=live |archive-url=https://web.archive.org/web/20191201110809/https://medlineplus.gov/ency/article/003516.htm |archive-date=2019-12-01 |access-date=2017-05-18 |website=medlineplus.gov |language=en}}{{Cite journal |last=Fried |first=Ari J. |last2=Bonilla |first2=Francisco A. |date=2017-05-19 |title=Pathogenesis, Diagnosis, and Management of Primary Antibody Deficiencies and Infections |journal=Clinical Microbiology Reviews |volume=22 |issue=3 |pages=396–414 |doi=10.1128/CMR.00001-09 |issn=0893-8512 |pmc=2708392 |pmid=19597006}}

Delayed hypersensitivity skin test
T cell count
Detection via culture(infection)

= Types =

== Primary or secondary ==

File:Lymphoma macro.jpg

Primary (or hereditary) immunodeficiencies of T cells include some that cause complete insufficiency of T cells, such as severe combined immunodeficiency (SCID), Omenn syndrome, and Cartilage–hair hypoplasia.
Secondary causes are more common than primary ones. Secondary (or acquired) causes are mainly:[https://books.google.com/books?id=iPuvQDcqW88C&pg=PA432 Page 432] {{Webarchive|url=https://web.archive.org/web/20230112210459/https://books.google.com/books?id=iPuvQDcqW88C&pg=PA432 |date=2023-01-12 }}, Chapter 22, Table 22.1 in: {{Cite book |last=Jones, Jane |title=Infection: Microbiology and Management |last2=Bannister, Barbara A. |last3=Gillespie, Stephen H. |publisher=Wiley-Blackwell |year=2006 |isbn=978-1-4051-2665-6}}

:*AIDS

:*Cancer chemotherapy

:*Lymphoma

:*Glucocorticoid therapy

===Complete or partial deficiency===

Complete insufficiency of T cell function can result from hereditary conditions (also called primary conditions) such as severe combined immunodeficiency (SCID), Omenn syndrome, and cartilage–hair hypoplasia.[http://emedicine.medscape.com/article/888372-overview Medscape > T-cell Disorders] {{Webarchive|url=https://web.archive.org/web/20191230120104/http://emedicine.medscape.com/article/888372-overview |date=2019-12-30 }}. Author: Robert A Schwartz, MD, MPH; Chief Editor: Harumi Jyonouchi, MD. Updated: May 16, 2011
Partial insufficiencies of T cell function include acquired immune deficiency syndrome (AIDS), and hereditary conditions such as DiGeorge syndrome (DGS), chromosomal breakage syndromes (CBSs), and B-cell and T-cell combined disorders such as ataxia-telangiectasia (AT) and Wiskott–Aldrich syndrome (WAS).

Treatment

File:US Navy 021204-N-0696M-171 Surgical technician Amina Sherali places recently transfused bone marrow from Aviation Electronics Technician 1st Class Michael Griffioen into a sterile bag in preparation for transplant.jpg

In terms of the management of T cell deficiency for those individuals with this condition the following can be applied:{{Cite web |title=Immunodeficiency (Primary and Secondary). Information. |url=https://patient.info/doctor/immunodeficiency-primary-and-secondary |url-status=live |archive-url=https://web.archive.org/web/20221221090119/https://patient.info/doctor/immunodeficiency-primary-and-secondary |archive-date=2022-12-21 |access-date=2017-05-18 |website=patient.info |language=en-GB}}

Killed vaccines should be used(not live vaccines in T cell deficiency)
Bone marrow transplant
Immunoglobulin replacement
Antiviral therapy
Supplemental nutrition

Epidemiology

In the U.S. this defect occurs in about 1 in 70,000, with the majority of cases presenting in early life.

Furthermore, SCID has an incidence of approximately 1 in 66,000 in California.{{Cite journal |date=2018-12-11 |title=B-Cell and T-Cell Combined Disorders: Background, Pathophysiology, Epidemiology |url=http://emedicine.medscape.com/article/885493-overview#a5 |url-status=live |archive-url=https://web.archive.org/web/20190414045306/https://emedicine.medscape.com/article/885493-overview#a5 |archive-date=2019-04-14 |access-date=2017-05-19}}