Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Up to 60% of cases of the autosomal recessive immunodeficiency hemophagocytic lymphohistiocytosis (HLH) are associated with mutations in the perforin (PRF1) gene. In this study, we expressed wild-type and mutated perforin in rat basophil leukemia cells to study the effect on lytic function of the substitutions A91V and N252S (commonly considered to be neutral polymorphisms) and 22 perforin missense substitutions first identified in HLH patients. Surprisingly, we found that A91V perforin was expressed at reduced levels compared with wild-type perforin, resulting in partial loss of lytic capacity. In contrast, expression and function of N252S-substituted perforin were normal. Most HLH-associated mutations resulted in protein degradation (probably due to misfolding) and complete loss of perforin activity, the exception being R232H, which retained approximately 30% wild-type activity. Several other mutated proteins (H222Q, C73R, F157V, and D313V) had no detectable lytic activity but were expressed at normal levels, suggesting that their functional defect might map downstream at the level of the target cell membrane. One further perforin substitution identified in an HLH patient (V183G) was normally expressed and displayed normal lysis. This report represents the first systematic functional analysis of HLH-associated missense mutations and the 2 most common perforin polymorphisms.
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PMID:A functional analysis of the putative polymorphisms A91V and N252S and 22 missense perforin mutations associated with familial hemophagocytic lymphohistiocytosis. 1575 97

X-linked lymphoproliferative disease (XLP) is an inherited immunodeficiency characterized by an extreme susceptibility to Epstein-Barr virus (EBV) infection. Patients with XLP mainly present with the 3 clinical manifestations of fulminant infectious mononucleosis, lymphoproliferative disorder, and dysgammaglobulinemia and in rare cases have aplastic anemia and lymphocytic vasculitis. The causative gene for XLP was identified as SH2D1A/DSHP/SLAM-associated protein (SAP) in 1998, and genetic analysis has been used for the definite diagnosis of XLP. Diagnosis for most patients occurs at ages younger than 10 years, and there are few adult patients. Here we describe a 23-year-old man with hypogammaglobulinemia and EBV-associated hemophagocytic lymphohistiocytosis and a diagnosis of XLP. In addition, the patient showed type 1 helper T-cell (Th1) skewing, as has been described in Sap knock-out mice. Th1/Th2 imbalance in humans, as well as in mice, may play an important role in the pathogenesis of XLP.
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PMID:X-linked lymphoproliferative disease in an adult. 1610 60

Griscelli syndrome (GS) was diagnosed in a 2-year-old patient with oculocutaneous albinism and immunodeficiency, but sequencing of RAB27a revealed only a heterozygous mutation. Due to impaired natural killer (NK) and T-cell cytotoxicity implying a high risk of developing hemophagocytic lymphohistiocytosis (HLH), he was prepared for hematopoietic stem cell transplantation (HSCT). Unexpectedly, a severe bleeding episode occurred that led to the demonstration of disturbed platelet aggregation, reduced plateletdense granules, and impaired platelet degranulation. In combination with neutropenia, this suggested the diagnosis of Hermansky-Pudlak syndrome type II (HPSII) and a novel homozygous mutation in AP3B1 was detected. None of the 3 reported HPSII patients had developed HLH, and our patient seroconverted to Epstein-Barr virus (EBV) without clinical symptoms. HSCT was therefore withheld, and granulocyte-colony-stimulating factor (G-CSF) therapy was initiated and prevented further bacterial infections. At 3 years of age, however, the patient developed, without an obvious trigger, fulminant HLH that was resistant to therapy. This patient shows that careful clinical and molecular diagnosis is essential to differentiate the complex disorders of lysosomal trafficking. HPSII belongs to the group of familial hemophagocytic syndromes and may represent an indication for HSCT.
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PMID:Lethal hemophagocytic lymphohistiocytosis in Hermansky-Pudlak syndrome type II. 1655 69

Hemophagocytic syndrome (HPS) is defined by bone marrow and organ infiltration by activated, nonmalignant macrophages, which phagocytose blood cells. The clinical spectrum of HPS is broad, but renal involvement has rarely been investigated. We report a previously unknown renal manifestation of HPS: nephrotic syndrome. This multicentric retrospective study included patients fulfilling the following criteria: (i) no history of nephropathy; (ii) HPS diagnosis with histologic evidence of hemophagocytosis; (iii) occurrence of nephrotic syndrome during HPS; and (iv) available renal histology. Using the same criteria, we also searched the literature for additional cases. We identified nine patients retrospectively and found two additional cases in the literature (five males and six females, whose mean age was 34 +/- 27 years). Black African patients predominated (63.6%). HPS was due to lymphoma (six cases), infectious disease (three cases), and autoimmune disease (one case), and was primary in one patient. Acute renal failure was associated with nephrotic syndrome in 10/11 cases. Renal histology showed acute tubular necrosis associated with collapsing glomerulopathy in five patients (all Africans with negative human immunodeficiency virus serology), minimal change glomerulopathy in four, and thrombotic-microangiopathy with abnormal podocytes in two. Death occurred in seven cases. Nephrotic syndrome should be included among the renal complications of HPS with acute renal failure. We postulate that abnormal T-cell activation and/or high pro-inflammatory cytokine levels during HPS might cause podocyte injuries, especially among African patients with a susceptible genetic background.
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PMID:Nephrotic syndrome associated with hemophagocytic syndrome. 1655 22

Hemophagocytic syndrome (HPS) is a rare condition characterized by overactive histiocytes, hepatosplenomegaly, fever and cytopenia, with two major types: familial, autosomal recessive genetic disease and acquired that can occur during systemic infections, immunodeficiency or malignancy. Inappropriate activation of macrophages by cytokines is the major mechanism of the disease. We report a case of an adult patient with HPS. After thorough clinical investigation, we have not been able to establish the underlying disease, and corticosteroids therapy was initiated empirically. After 8 months follow-up the patient is well with normal laboratory findings.
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PMID:Hemophagocytic syndrome--should we consider it more often? 1724 73

Hemophagocytic syndrome (HS) may occur as a consequence of herpes viral infections. Human herpesvirus 8 (HHV-8)/Kaposi sarcoma-associated herpesvirus has so far been recognized as a trigger of HS only in immunosuppressed subjects or in patients with Kaposi sarcoma and/or HHV-8-related lymphoproliferative diseases. We report two Italian human immunodeficiency virus (HIV)-negative elderly men who developed an HS with a rapidly fatal course, following treatment with corticosteroids for autoimmune hemolytic anemia. An overwhelming active infection with HHV-8 was unequivocally documented by molecular and immunohistochemical methods, in the absence of HHV-8-related tumors. The occurrence of HHV-8-associated HS, although rare, may be considered, even out of the HIV or the transplantation settings, at least in areas endemic for HHV-8 infection.
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PMID:Fatal hemophagocytic syndrome related to active human herpesvirus-8/Kaposi sarcoma-associated herpesvirus infection in human immunodeficiency virus-negative, non-transplant patients without related malignancies. 1733 Nov 29

A rare complication of infection with the Epstein-Barr virus is the development of hemophagocytic lymphohistiocytosis. Although most cases of Epstein-Barr virus-induced hemophagocytic lymphohistiocytosis develop in immunocompetent individuals, the rare immunodeficiency X-linked lymphoproliferative disease is often unmasked by Epstein-Barr virus infection and is clinically indistinguishable from Epstein-Barr virus-induced hemophagocytic lymphohistiocytosis. We describe the clinical course and management of a previously healthy 17-year-old boy who presented with hemodynamic collapse and severe systemic inflammatory response syndrome resulting from overwhelming hemophagocytosis in the setting of X-linked lymphoproliferative disease. A novel therapeutic approach using anti-tumor necrosis factor alpha therapy was instituted, aimed at attenuating the viral-induced hyperinflammatory state. Given the similarity to overwhelming sepsis, yet a substantially different therapeutic approach, this case illustrates the importance of early recognition and prompt treatment that are necessary to reduce the high morbidity and mortality associated with Epstein-Barr virus-induced hemophagocytic lymphohistiocytosis and X-linked lymphoproliferative disease.
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PMID:Epstein-Barr virus-induced hemophagocytic lymphohistiocytosis and X-linked lymphoproliferative disease: a mimicker of sepsis in the pediatric intensive care unit. 1740 20

The spread of human immunodeficiency virus (HIV) infection has exploded over the past two decades and such infections in young people are no longer uncommon. However, the major infection route of pediatric patients remains vertical transmission, and sexual, especially homosexual transmission, is highly unusual. We herein describe the case of a 17-year-old boy who developed hemophagocytic lymphohistiocytosis (HLH). Although HLH was remitted soon with dexamethasone therapy, an HIV infection caused by homosexual transmission was detected.
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PMID:Hemophagocytic lymphohistiocytosis in a human immunodeficiency virus-positive homosexual high school student. 1804 10

Hemophagocytic lymphohistiocytosis (HLH) has been described in patients with advanced stages of human immunodeficiency virus (HIV) infection, but rarely occurs during the seroconversion stage of acute HIV infection. We report a case of acute HIV syndrome that presented with virus-associated HLH. The patient recovered spontaneously without any immunomodulating therapy. This case suggests that acute HIV infection should be included in the differential diagnosis of HLH and indicates that HLH associated with acute HIV infection can have a favorable outcome.
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PMID:Acute human immunodeficiency virus syndrome presenting with hemophagocytic lymphohistiocytosis. 1845 72

Griscelli syndrome (GS) is a rare autosomal recessive disease characterized by silvery hair ('partial albinism'). Three forms exist; GS type 2 (GS2), the most common one, is characterized by severe primary immunodeficiency with acute episodes of hemophagocytic lymphohistiocytosis (HLH) which may be fatal in the absence of hematopoietic stem cell transplantation. A 5-year-old boy with HLH was referred to us because of silvery-gray hair present since birth. Abnormal pigment clumps were observed in the medulla of hair shafts on light microscopy. Electron microscopy of a skin biopsy revealed melanosomes in melanocytes, but not in keratinocytes. Leukocytes were devoid of intracytoplasmic granules on blood smear. Neurological signs were absent. Genotyping revealed a homozygous haplotype for polymorphic markers linked to the RAB27A locus, but no RAB27A mutation. A diagnosis of GS2 was established. The patient received bone marrow transplantation (BMT) from an unrelated donor, and after 72 months he did not show relapse of HLH. The long, uneventful follow-up supports the use of BMT from an unrelated donor if transplantation from a relative is not possible.
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PMID:Griscelli syndrome type 2: long-term follow-up after unrelated donor bone marrow transplantation. 1927 Apr 33


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