Purine nucleoside phosphorylase deficiency

Infobox_Disease
Name = PAGENAME


Caption =
DiseasesDB = 11044
ICD10 = ICD10|D|81|5|d|80
ICD9 = ICD9|277.2
ICDO =
OMIM = 164050
MedlinePlus =
eMedicineSubj = ped
eMedicineTopic = 1957
MeshID =

Purine nucleoside phosphorylase deficiency, often called PNP-deficiency, is a very rare autosomal recessive metabolic disorder which results in severe combined immunodeficiency.

Causes

It is to a disruption of the purine nucleoside phosphorylase enzymatic pathway.

This enzyme is required for purine degradation. A deficiency of it also causes T-cell deficiency.cite journal |author=Snyder FF, Jenuth JP, Mably ER, Mangat RK |title=Point mutations at the purine nucleoside phosphorylase locus impair thymocyte differentiation in the mouse |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=94 |issue=6 |pages=2522–7 |year=1997 |month=March |pmid=9122228 |pmc=20121 |doi= |url=http://www.pnas.org/cgi/pmidlookup?view=long&pmid=9122228] cite journal |author=Toro A, Grunebaum E |title=TAT-mediated intracellular delivery of purine nucleoside phosphorylase corrects its deficiency in mice |journal=J. Clin. Invest. |volume=116 |issue=10 |pages=2717–26 |year=2006 |month=October |pmid=16964310 |pmc=1560347 |doi=10.1172/JCI25052 |url=http://dx.doi.org/10.1172/JCI25052]

In contrast to adenosine deaminase deficiency (another deficiency of purine metabolism), there is minimal disruption to B cells.cite web |url=http://www.emedicine.com/ped/TOPIC1957.HTM |title=eMedicine - Purine Nucleoside Phosphorylase Deficiency : Article by Alan P Knutsen |format= |work= |accessdate=]

ymptoms

In addition to the symptoms associated with immunodeficiency, such as depletion of T-cells, decline of lymphocyte activity, and an abrupt proliferation of both benign and opportunistic infections, PNP-deficiency is often characterized by the developement of autoimmune disorders. Lupus-erythematosis, autoimmune hemolytic anemia, and idiopathic thrombocytopenic purpura have been reported with PNP-deficiency.cite journal |author=Markert ML |title=Purine nucleoside phosphorylase deficiency |journal=Immunodefic Rev. |volume=3 |issue=1 |pages=45–81 |year=1991 |pmid=1931007 ]

Neurological symptoms, such as developmental decline, hypotonia, and mental retardation have also been reported.

Genetic prevalence

PNP-deficiency is extremely rare. Only 33 patients with the disorder in the United States have been documented.

References