Untitled - D Ank Unlimited

chronic and cyclic neutropenia 169 chronic graft-vs.-host disease (GVHD)
inflammation and necrosis are followed by fibrosis and
cirrhosis. The T cells infiltrating the liver are CD4 + . Plasma
cells are also present, and immunoglobulins may be deposited
on hepatocytes. The autoantibodies against liver cells
do not play a pathogenetic role in liver injury. No serologic
findings are diagnostic. Corticosteroids are useful in treatment.
The immunopathogenesis of autoimmune chronic
active hepatitis involves antibody, K cell cytotoxicity, and T
cell reactivity against liver membrane antigens. Antibodies
and specific T suppressor cells reactive with LSP are found
in chronic active hepatitis patients, all of whom develop T
cell sensitization against asialo-glycoprotein (AGR) antigen.
Chronic active hepatitis has a familial predisposition.
chronic and cyclic neutropenia
A syndrome characterized by recurrent fever, mouth ulcers,
headache, sore throat, and furunculosis occurring every 3
weeks in affected individuals. This chronic agranulocytosis
leads to premature death from infection by pyogenic
microorganisms in affected children who may have associated
pancreatic insufficiency, dysostosis, and dwarfism.
Antibodies can be transmitted from the maternal to fetal
circulation to induce an isoimmune neutropenia that may
consist of a transitory type in which the antibodies are
against neutrophil antigens determined by the father or a
type produced by autoantibodies against granulocytes.
chronic asthma
A clinical condition in which the airways are chronically
inflamed, leading to difficulty in breathing. Whereas
exposure to an allergen may initiate the condition, chronic
asthma may progress in its absence.
chronic disease
A malady, such as a persistent infection, characterized by
persistent or recurring symptoms.
chronic fatigue syndrome (CFS)
A disabling fatigue that persists for at least 6 months.
Although the etiology is idiopathic, laboratory studies on
patients reveal a consistent observation of immune system
dysfunction primarily affecting the cellular immune
response. CD4 + T helper cells and CD8 + suppressor/
cytotoxic cells may be normal, increased, or decreased,
but the CD4/DC8 ratio is usually elevated. This has been
attributed to a diminished number of suppressor cells with
a concomitant increase in cytotoxic T cell (CD8 + , CD28 + ,
CD11b–) numbers. The increased cytotoxic T cells express
HLA–DR and/or CD38 activation markers. Manifestations
of altered T cell functions also include decreased delayedtype
hypersensitivity, diminished responsiveness in
mitogen-stimulation assays in vitro, increased suppression
of immunoglobulin synthesis by T cells, and elevated
spontaneous suppressor activity. Natural killer (NK) cells
may be normal, increased, or decreased, but there may be
qualitative alterations in NK cell function. Elevated immunoglobulin
G (IgG) antibody titers to Epstein–Barr virus
(EBV) early antigen and capsid antigen are demonstrable
in many CFS patients. Occasionally, increased antibodies
against cytomegalovirus (CMV), herpes simplex, human
herpesvirus type 6 (HHV-6), coxsackie B, or measles may
be observed. Some CFS patients have abnormal levels of
IgG, IgM, IgA, or IgD. Approximately one third of CFS
patients have antibodies against smooth muscle or thyroid.
Laboratory test results from CFS patients should be interpreted
as one battery and not as individual tests.
Chronic graft-vs.-host disease (GVHD) of the liver with pronounced
inflammation and portal fibrosis with disappearance of bile ducts.
chronic graft rejection (CGR)
An anti-allograft immune response with features of fibrosis,
collagen deposition and chronic graft vasculopathy that
appear several months following transplantation and lead to
cessation of allograft function.
chronic graft-vs.-host disease (GVHD)
Chronic GVHD may occur in as many as 45% of long-term
bone marrow transplant recipients. It differs both clinically
and histologically from acute GVHD and resembles
autoimmune connective tissue diseases. For example,
chronic GVHD patients may manifest skin lesions resembling
scleroderma; sicca syndrome in the eyes and mouth;
inflammation of the oral, esophageal, and vaginal mucosa;
bronchiolitis obliterans; occasionally myasthenia gravis;
polymyositis; and autoantibody synthesis. Histopathologic
alterations in chronic GVHD, such as chronic inflammation
and fibrotic changes in involved organs, resemble changes
associated with naturally occurring autoimmune disease.
The skin may reveal early inflammation with subsequent
fibrotic changes. Infiltration of lacrimal, salivary, and
submucosal glands by lymphoplasmacytic cells leads
ultimately to fibrosis. The resulting sicca syndrome that
resembles Sjögren’s syndrome occurs in 80% of chronic
GVHD patients. Drying of mucous membranes in the
sicca syndrome affects the mouth, esophagus, conjunctiva,
urethra, and vagina. The pathogenesis of chronic GVHD
involves the interaction of alloimmunity, immune dysregulation,
and resulting immunodeficiency and autoimmunity.
The increased incidence of infection among chronic GVHD
patients suggests immunodeficiency. The dermal fibrosis is
associated with increased numbers of activated fibroblasts
in the papillary dermis. T lymphocyte or mast cell cytokines
may activate this fibroplasia, which leads to dermal
fibrosis in chronic GVHD.
Nitroblue tetrazolium test (NBT) for diagnosis in CGD.
C