Transcript Hemophagocytic Syndromes for heme_onc

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Brant Ward, MD, PhD
Allergy & Immunology
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Recognize the diagnostic criteria for HLH
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Become familiar with the genetic and mechanistic causes
of HLH
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Describe the differences between genetic and acquired
forms of HLH
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Formulate an effective treatment plan
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Pathologic finding of
phagocytosis of red blood
cells, leukocytes, and
thrombocytes by
macrophages
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Thought to occur after
over-activation of
macrophages due to
dysregulated immune
responses
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In 1939, Scott & Robb-Smith described patients with
“atypical Hodgkin’s disease” – proliferation of histiocytes
affecting all lympho-reticular tissues
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Farquhar & Claireaux described a familial syndrome with
similar features in 1952
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Hallmark clinical features include fever, splenomegaly, and
cytopenias; hepatitis, altered mental status, and
neurological involvement seen as well
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Syndromes characterized by hemophagocytosis are termed
‘hemophagocytic lymphohistiocytsis’ (HLH)
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Diagnostic criteria for HLH were proposed by the Histiocyte
Society in 1991
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Five of the eight following criteria must be present to make
the diagnosis:
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Alternatively, identification of one of the known genetic
• Fever
defects• associated
disease
Cytopenias inwith
2 of 3the
lineages
• Splenomegaly
 Ferritin •is Hypertriglyceridemia
the most sensitive
at hypofibrinogenemia
discerning HLH from other
and/or
• Hemophagocytosis
disorders
• Low or absent NK cell activity
o Ferritin
>10,000 ng/ml is >90% specific for HLH in children
• Hyperferritinemia
• Elevated plasma levels of soluble CD25
o Ferritin >50,000 ng/ml is less specific in adults, but still very
sensitive
Perforin
deficiency
Helminthic
infections
Munc 13-4
deficiency
Syntaxin 11
deficiency
Munc 18-2
deficiency
Fungal infections
HLH
Unknown gene
mutations
Immune
deficiencies
Bacterial
infections
Viral infections
Medications
Malignancy
Autoimmune
diseases
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Genetic HLH
o Disorders characterized by elevated risk for HLH
o Includes Familial Hemophagocytic Lymphohistiocytosis (FHL) as well
as certain immunodeficiencies
o Caused by defects in the cell-mediated cytotoxicity pathways
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Acquired HLH
o A.k.a., Reactive Hemophagocytic Lymphohistiocytosis (RHL)
o Varied group of disorders that result in hemophagocytic symptoms
o Caused by dysregulated immune responses leading to lymphocyte
and macrophage activation
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FHL can be divided into 5 subtypes:
o FHL1 – caused by unknown defect on chromosome 9
o FHL2 – caused by deficiency of Perforin
o FHL3 – caused by deficiency of Munc 13-4
o FHL4 – caused by deficiency of Syntaxin 11
o FHL5 – caused by deficiency of Munc 18-2
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Chediak-Higashi & Griscelli II syndromes are characterized
by partial albinism and immune deficiency
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XLP is characterized by massive lymphoproliferation and
immune deficiency
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Sometimes referred to as Farquhar’s disease after its
describer (1952)
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Autosomal recessive inheritance with estimated incidence
of 1:50,000 live births (male > female)
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Symptoms are usually evident by 1 year (70-80% of case)
and can even present at birth or in utero
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Some forms can present in later childhood or even as
adults
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Overwhelming HLH is the primary symptom, and deficient
NK cell-mediated cytotoxicity is characteristic
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Identified from four consanginous families of Pakistani
descent using homozygosity mapping
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First defined susceptibility locus for FHL, located at
9q21.3-22
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This locus contains hundreds of candidate genes, though
none have been identified as the culprit
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Perforin (PRF1) was the first
identified gene causing FHL
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>70 different mutations have
been identified
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Trp374 stop has high
incidence in Turkish families
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L364 frame-shift is found in
Japanese families
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L17 frameshift found in
families of African origin
Stepp, et al. Science. 1999 Dec 3;286(5446):1957-9.
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Protein found in lytic granules of NK cells and cytotoxic T
lymphocytes
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Contains MACPF domain that shares a high degree of
homology with complement proteins C6-9
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Oligomerizes within the membrane of target cell, forming a
channel in the membrane
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Perforin alone is sufficient to lyse target cells at high (i.e.,
non-physiologic) concentrations
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Perforin channels allow entry of granzymes from the
immune synapse into the target cell cytoplasm
Kondos, et al. Tissue Antigens. 2010 Nov;76(5):341-51.
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Due to mutations in Munc 13-4
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Identified from 7 affected
families (6 consanguinous)
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Munc 13-4 defiency accounts
for 30-35% of cases
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Together with perforin gene
mutations, cause up to 70% of
FHL cases
Feldmann, et al. Cell. 2003 Nov 14;115(4):461-73.
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Member of the Munc 13-UNC 13 family of proteins
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Many expressed at the neurological synapse, acting as
priming factors for synaptic vesicle secretion
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Deficiency causes impaired release of cytotoxic granules
from cells, but no affect on interferon- secretion
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Munc 13-4 is required for priming of lytic granules that are
docked at the plasma membrane
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Goblet cells in lung epithelium express high levels of Munc
13-4, but deficiency causes no observable lung pathology
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Mutations in syntaxin 11
characterize FHL4
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Identified in a large
consanguineous Kurdish
family
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All identified mutations in
are null mutations
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Syntaxin mutations account
for ~20% of FHL cases in
Turkish and Kurdish
populations
zur Stadt, et al. Hum Mol Genet. 2005 Mar 15;14(6):827-34.
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Soluble N-ethylmaleimide sensitive factor attachment
protein receptor (SNARE) family member
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Phylogenetically related to the target membrane SNARE (tSNARE) proteins syntaxin 1-4
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Selective pairing of t-SNARE, v-SNARE, and adaptor proteins
form a stable parallel four helical bundle
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Deficiencies cause defects in NK cell, but not CTL, cytotoxic
activity, which is partially rescued by IL-2
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FHL4 phenotype does not differ from that of FHL 2 or 3
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Results from deficiency of
Munc 18-2
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Identified in patients of
African, Arabian, Turkish,
and European descent
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Phenotype appears to
correlate with genotype
based on age of onset and
severity of disease
Cote, et al. J Clin Invest. 2009 Dec;119(12):3765-73.
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Also called syntaxin-binding-protein-2 (STXBP2)
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Member of SM family of fusion accessory proteins —
complimentary role with SNAREs in membrane fusion
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Syntaxin 11 expression is impaired in Munc 18-2 deficient
cells , suggesting a requirement for Munc18-2
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From data on Munc 18-1, Munc 18-2/syntaxin 11 complex
regulates docking and initiation of SNARE complex
formation
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Pigmentary dilution, HLH,
defective NK, T cell, &
neutrophil function
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HLH typically occurs later
than in FHL (2-10 years)
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Light complexion, silvery
hair, and characteristic
peripheral nerve disease
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Infections are common, due
to inability to kill organisms
after phagocytosis
Reddy, et al. Int J Trichology. 2011 Jul;3(2):107-11.
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Caused by mutation in CHSI/LYST, a ubiquitously-expressed
protein
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Function of LYST has been inferred from studies of other
BEACH family proteins
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May regulate sorting of endosomal proteins into lysosomes
or regulate fusion or fission events of lysosomes
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Striking feature is the occurrence of giant intra-cytoplasmic
lysosomal structures in all granulated cells, with lack of
degranulation upon stimulus
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Pigmentary dilution, HLH,
and pyogenic infections
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Onset of HLH is later than
in FHL (median age 3
years)
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Patients have silvery hair
and light skin
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NK cells and CTLs show
impaired degranulation
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Caused by mutations in the gene encoding Rab27a, a
ubiquitously expressed small GTPase
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Enriched on endosomal structures that fuse with cytotoxic
granules before release of their contents
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Deficiency renders cytotoxic granules unable to reach the
immune synapse to dock with the plasma membrane
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Interacts with Munc 13-4 to coordinate the final step of the
exocytic process, between docking and priming of the
granule
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X-linked lymphoproliferative disorder—characterized by
hypogammaglobulinemia or lymphoproliferation
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Caused by mutations in SLAM-associated protein (SAP) or Xlinked inhibitor of apoptosis (XIAP)
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Epstein-Barr virus infection results in fulminant and fatal
mononucleosis
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HLH is almost always associated with EBV infection
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SAP deficiency results in a partial cytotoxic defect; no
observable cytotoxic defect in XIAP deficiency
Vesicle Maturation
(LYST)
Vesicle Priming
(Munc 13-4)
Vesicle Fusion
(Syntaxin 11/Munc 18-2)
Vesicle Docking
(Rab27a)
Effector Function
(Perforin)
Virus-infected
Cells
CTL
IFN-
APC
Virus-infected
Cells
CTL
IFN-
APC
CTL
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Perforin deficient mice with HLH have normal total amount
of dendritic cells, but…
Terrell & Jordan. Blood. 2013 Jun 27;121(26):5184-91.
Jordan, et al. Blood. 2004 Aug 1;104(3):735-43.
Jordan, et al. Blood. 2004 Aug 1;104(3):735-43.
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The cytokines production and immune activation triggered
by these cells is thought to cause the observed symptoms
o Fever is induced by overproduction of IL-1
o Pancytopenia is a consequence of TNF and IFN
o Activated macrophages actively secrete ferritin
o Macrophages also secrete plasminogen activator, leading to
consumption of plasma fibrinogen
o Activated lymphocytes secrete soluble CD25 and infiltrate the liver
and central nervous system
o Proliferation of macrophages expressing CD163 in marrow and
lymphoid tissue leads to hemophagocytosis
Spectrum of Cytokine-Induced Disease
Macrophage
activation
syndrome
Genetic
HLH
Acquired
HLH
SIRS
Severe
sepsis
Normal
response
to infxn
Schaer, et al. Eur J Haematol. 2006 Nov;77(5):432-6.
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First description of the disorder may have been as early as
1970s
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‘Macrophage activation syndrome’ (MAS) first used in 1992
by Albert, et al.
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MAS occurs in both children and adults with autoimmune
syndromes
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Characterized by cytopenias, organ dysfunction,
coagulopathy, and inappropriate activation of macrophages
in a proinflammatory milieu
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MAS can be associated with a wide variety of autoimmune
diseases
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Strongest associations is with systemic juvenile idiopathic
arthritis (sJIA), with estimated clinically apparent MAS in 713% of subjects
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Subclinical bone marrow evidence of MAS in >50% of sJIA
patients
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However, MAS also occurs with SLE and adult-onset Still’s
disease, along with multiple other diseases
Autoimmune Diseases Associated with MAS
Adult-onset Still’s disease
Ankylosing spondylitis
Dermatomyositis
Enthesitis-related arthritis
Inflammatory bowel disease
Kawasaki disease
Polyarticular JIA
Sarcoidosis
Systemic JIA
Systemic lupus erythematosus
Unidentified autoimmune disease
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sJIA and other autoimmune conditions are associated with
fevers, anemia, hepatosplenomegaly, lymphadenopathy,
and elevated serum ferritin
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Ravelli, et al., defined a set of criteria for the diagnosis of
MAS in patients with sJIA
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A number of characteristic findings on routine studies were
also identified
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Subsequent investigation demonstrated that the criteria do
not always apply to MAS in other autoimmune conditions
Laboratory Criteria
Value
Thrombocytopenia
≤ 262 x 106/l
Elevation in AST
> 59 U/L
Leukocytosis
≤ 4.0 x
106/l
Hypofibrinogenemia
≤ 250 mg/dL
Clinical Criteria
Manifestation
CNS dysfunction
Irritability
Headache
Lethargy
Disorientation
Seizures
Coma
Hemorrhages
Ecchymoses
Purpura
Mucosal bleeding
Hepatomegaly
≥ 3 cm below costal margin
Diagnosis requires:
>2 Laboratory criteria
>2 Lab + Clinical criteria
Addition of ferritin >500
ng/ml may better
discriminate MAS vs
systemic infection.
Adapted from: Davi, et al. Arthritis
Rheumatol. 2014 Oct;66(10):2871-80.
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In 1979, Risdall, et al., described 19 patients with evidence
of HLH and viral infection after transplantation
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Later, it was shown that most patients had no evidence of
immune system dysfunction before developing RHL
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‘Virus associated hemophagocytic syndrome’ was used to
denote any case of HLH without a genetic cause
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Eventually, bacteria, fungi, and even protozoa were shown
to trigger RHL, leading to the term ‘infection associated
hemophagocytic syndrome’ (IAHS)
Infections Associated with HLH
Epstein-Barr virus
Escherichia coli
Cytomegalovirus
Salmonella sp.
Varicella virus
Enterococcus sp.
HHV6
Mycoplasma sp.
Parvovirus B19
Tick-born bacteria
Hepatitis A
Tuberculosis
HIV
Visceral leishmaniasis
Adenovirus
Plasmodium sp.
Influenza
Toxoplasma sp.
Coxsackievirus
Pneumocystis jiroveci
Torovirus
Candida sp.
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EBV is the most common infectious trigger of RHL,
accounting for 74% of viral triggers in one study
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EBV carries the worst prognosis among viral triggers, with
73% mortality in one case series (before HLH ’04)
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Incidence is highest in east Asians countries, possibly due
to more-virulent endemic strain
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Rarely detected in B-cell lymphoma-associated RHL;
present in 80% with T/NK cell lymphoma-triggered RHL
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Mortality was found to be 14x higher in EBV-associated RHL
patients who did not receive etoposide
Medications Associated with HLH
Aspirin
Morniflumate
NSAIDs
Methotrexate
Sulfasalazine
Infliximab
Etanercept
Penicillamine
Anakinra
Vancomycin
Gold salts
Parenteral lipids
Autologous stem cell transplantation
Included Parameters
Known underlying immunosuppression
Temperature
Organomegaly
No. of cytopenias
Ferritin
Triglycerides
Fibrinogen
AST
Hemophagocytosis on BM biopsy
Freely available at:
http://saintantoine.aphp.fr/score/
Fardet, et al. Arthritis Rheumatol. 2014 Sep;66(9):2613-20.
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Adult-onset HLH has been associated with homozygous and
heterzygous mutations in multiple FHL genes
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Striking number variants of FHL-associated genes have
been identified in MAS patients
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Current recommendation is to perform genetic analyses on
ALL patients suspected or confirmed to have HLH
Kaufman, et al. Arthritis Rheumatol. 2014 Dec;66(12):3486-95.
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Finally!
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Immediate aim is to suppress over-whelming inflammation
and immune activation; many different agents have been
tried
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In 1991, the Histiocyte Society developed the HLH 94
treatment protocol, improving survival in pediatric
populations from ~25% to 51-55%
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In 2002, Henter, et al., showed an overall survival rate of
80% in patients that underwent HSCT
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Histiocyte Society updated the treatment protocol in 2004,
including new treatments such as HSCT
Systemic Therapy
Dexamethasone
Etoposide
Cyclosporine
Week 1
10 mg/m2 daily
150 mg/m2 IV biw
3 mg/kg bid
Week 2
10 mg/m2 daily
150 mg/m2 IV biw
To Trough 200 g/L
Week 3
5 mg/m2 daily
150 mg/m2 IV qwk
To Trough 200 g/L
Week 4
5 mg/m2 daily
150 mg/m2 IV qwk
To Trough 200 g/L
Week 5
2.5 mg/m2 daily
150 mg/m2 IV qwk
To Trough 200 g/L
Week 6
2.5 mg/m2 daily
150 mg/m2 IV qwk
To Trough 200 g/L
Week 7
1.25 mg/m2 daily
150 mg/m2 IV qwk
To Trough 200 g/L
Week 8
Taper and d/c
150 mg/m2 IV qwk
To Trough 200 g/L
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Applicability of HLH 04 protocol to RHL syndromes (e.g.,
MAS) and to adult populations is not been established
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Mutliple groups support a graded-approach, with
corticosteroids alone as initial treatment
Initial Therapy
High-dose corticosteroids (prednisolone 30 mg/kg x3 days)
Elimination of suspected triggers, infection control
Aggressive supportive measures
Secondary Therapy
Intravenous immunoglobulin (1-3 g/kg)
Cyclosporine A, etoposide
Proposed Treatments for Autoimmune-Associated HLH
Cyclosporine A
Plasmaphoresis
Etanercept
Abatacept
Anakinra
Antithymocyte globulin
Intravenous immunoglobulin
Corticosteroids
Etoposide
Naproxen
Splenectomy
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Several series suggest outcomes are poor in RHL if
infection control measures are used alone
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RHL triggered by leishmaniasis may be treated solely with
amphotericin
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Etoposide is crucial for EBV-associated RHL — inhibits
activated T cells, plus EBV NA in infected cells
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Multiple groups agree that HLH 2004 should be initiated for
relapses of RHL, despite etiology
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HSCT has best overall outcome among all single treatment
modalities across all patient populations
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HLH is a clinical syndrome of overwhelming immune
activation and cytokine production
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Cytokine storm in HLH occurs due to failure to clear antigen
presenting cells and/or activated T cells
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Genetic variants may predispose patients to HLH at any age
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Treatment is aimed at controlling the inflammatory cytokine
cascade, and may require BMT in severe cases