Clinical aspects and main diagnostic methods of Chediak-Higashi syndrome

Chediak-Higashi syndrome is a disorder caused by a mutation in the LYST gene and characterized by immunodeficiency, oculocutaneous albinism, and neurological dysfunction resulting from changes in neutrophils. Homozygotes die in the first decade of life. The study is a literature review from different sources. We extracted articles published between 2000 and 2018 from SciELO, LILACS, MEDLINE (via PubMed), and Google Scholar databases. Our main objective was to report pathophysiology, clinical presentation, and the most common diagnostic methods. The syndrome affects the hematological and neurological systems, and laboratory diagnosis is first made by the presence of giant granules in leukocytes, mainly neutrophils in peripheral blood and bone marrow. A definitive diagnosis is made by cytochemical reaction (myeloperoxidase) and detection of mutation by molecular methods. (AU)

Neutrophil phenotypes in chronic lung disease.

Introduction: Neutrophils are the most abundant inflammatory cells in the lungs of patients with chronic lung diseases, especially COPD, yet despite this, patients often experience repeated chest infections. Neutrophil function may be altered in disease, but the reasons are unclear. In chronic disease, sequential pro-inflammatory and pro-repair responses appear distorted. As understanding of neutrophil heterogeneity has expanded, it is suggested that different neutrophil phenotypes may impact on health and disease. Areas covered: In this review, the definition of cellular phenotype, the implication of neutrophil surface markers and functions in chronic lung disease and the complex influences of external, local and genetic factors on these changes are discussed. Literature was accessed up to the 19 July 2019 using: PubMed, US National Library of Medicine National Institutes of Health and the National Centre for Biotechnology Information. Expert opinion: As more is learned about neutrophils, the further we step from the classical view of neutrophils being unrefined killing machines to highly complex and finely tuned cells. Future therapeutics may aim to normalize neutrophil function, but to achieve this, knowledge of phenotypes in humans and how these relate to observed pathology and disease processes is required.

The neuropsychological phenotype of Chediak-Higashi disease.

BACKGROUND/OBJECTIVES: Chediak-Higashi Disease (CHD) is a rare autosomal disorder, purported to have cognitive and neurological impairments. Prior descriptions of cognitive impairment, however, are solely based on subjective, unstructured observations rather than on formal neuropsychological measures. METHODS: Four pediatric and 14 adult patients with diagnostically confirmed CHD were administered a neuropsychological battery assessing memory, attention, processing speed, psychomotor speed, language fluency, executive function, and general intelligence. Nine of the adult patients received follow-up evaluations to elucidate the longitudinal progression or stability of cognition over time. RESULTS: Pediatric CHD patients performed within the average range. Adult patients, however, performed below average on nearly all measures administered, and endorsed subjective reports of learning difficulties and poor academic performance in childhood. In particular, patients struggled with memory and psychomotor speed tasks, with 75% or more of patients scoring in the bottom 2.3 percentile in these two domains. No significant declines in cognition were observed among the patients who completed follow-up evaluations (M = 39.90, SD = 8.03 months between visits). Exploratory analyses suggested that adult patients who had classic CHD and previously received bone marrow transplants (BMTs; n = 3) exhibited moderately greater cognitive impairment than adult patients who had atypical CHD and had not received BMTs (n = 10). CONCLUSIONS: Adult patients with CHD uniformly exhibit deficits in multiple domains, but in psychomotor speed and memory, in particular. Based on their neuropsychological profile, their ability to hold jobs and succeed in school may require support and special accommodations. The source of cognitive deficits is probably multifactorial including central nervous system involvement in CHD, and, for those transplanted, BMT-related side effects and complications. Absence of cognitive decline at three-year follow-up is encouraging but does not exclude progression at a slower time-scale. Future work should elucidate the possible effects and timing of BMT on cognition, as well as the mechanisms driving neuropsychological impairment in CHD.

Inflammatory demyelinating neuropathy heralding accelerated chediak-higashi syndrome.

INTRODUCTION: Chediak-Higashi syndrome (CHS) is a very rare autosomal recessive disorder (gene CHS1/LYST) characterized by partial albinism, recurrent infections, and easy bruising. Survivors develop a constellation of slowly progressive neurological manifestations. METHODS: We describe clinical, laboratory, electrophysiological, and genetic findings of a patient who developed an immune-mediated demyelinating neuropathy as the main clinical feature of CHS. RESULTS: The patient presented with subacute flaccid paraparesis, absent reflexes, and reduced vibration sense. Protein and immunoglobulins (Igs) were elevated in the cerebrospinal fluid. Electrodiagnostic tests indicated an acquired chronic demyelinating polyneuropathy. Intravenous Ig and immunosuppressant treatment resulted in neurological improvement. The patient later developed organomegaly and pancytopenia. Bone-marrow smear revealed giant azurophilic granules pathognomonic for CHS. Two novel mutations in the LYST gene were identified through whole exome sequencing [c.7786C>T and c.9106 + 1G>T]. CONCLUSIONS: This case expands the clinical phenotype of CHS and highlights inflammatory demyelinating neuropathy as a manifestation of the disease. Muscle Nerve 55: 756-760, 2017.

Concordance of visual and structural features between siblings with albinism.

PURPOSE: To evaluate similarities and differences in visual function and ocular structure between siblings with albinism. METHODS: The medical records of all siblings diagnosed with albinism were retrospectively reviewed. Comparisons were made using examination at oldest age for younger sibling and examination closest to that age for older siblings. RESULTS: A total of 111 patients from 54 families were studied. Mean age was 12.9 years (range, 2 months to 44.2 years). Mean difference in ages between sibling pair examinations was 11.5 months (range, 0-87 months). Of 45 families, best-corrected visual acuity was equal in 9 (20%), within 1/2 octave in 9 (20%), >1/2 but <1 octave in 21 (47%), and ≥1 octave difference in 6 (13%). Of 27 families, stereoacuity was present in all siblings in 9 (33%), absent in 9 (33%), and present in only 1 sibling in 9 (33%). Of 54 families, grading of iris translucency was equal in 35 (65%) and different by 1 grade in 19 (35%). Of 54 families, foveal grading was equal in 39 (72%), different by 1 grade in 14 (26%), and different by ≥2 grades in 1 (2%). Macular melanin was present in all siblings in 16 of the 54 families (30%), absent in all siblings in 36 (67%), and present in only 1 sibling in 2 (4%) families. CONCLUSIONS: The strong concordance of structural features is contrasted with discordance in visual function. Families of siblings with albinism should be counseled with due caution because visual function is often disparate despite similar structural findings.

Lysosomal Trafficking Regulator (LYST).

Regulation of vesicle trafficking to lysosomes and lysosome-related organelles (LROs) as well as regulation of the size of these organelles are critical to maintain their functions. Disruption of the lysosomal trafficking regulator (LYST) results in Chediak-Higashi syndrome (CHS), a rare autosomal recessive disorder characterized by oculocutaneous albinism, prolonged bleeding, severe immunodeficiency, recurrent bacterial infection, neurologic dysfunction and hemophagocytic lympohistiocytosis (HLH). The classic diagnostic feature of the syndrome is enlarged LROs in all cell types, including lysosomes, melanosomes, cytolytic granules and platelet dense bodies. The most striking CHS ocular pathology observed is an enlargement of melanosomes in the retinal pigment epithelium (RPE), which leads to aberrant distribution of eye pigmentation, and results in photophobia and decreased visual acuity. Understanding the molecular function of LYST and identification of its interacting partners may provide therapeutic targets for CHS and other diseases associated with the regulation of LRO size and/or vesicle trafficking, such as asthma, urticaria and Leishmania amazonensis infections.

Chediak-Higashi syndrome: Lysosomal trafficking regulator domains regulate exocytosis of lytic granules but not cytokine secretion by natural killer cells.

BACKGROUND: Mutations in lysosomal trafficking regulator (LYST) cause Chediak-Higashi syndrome (CHS), a rare immunodeficiency with impaired cytotoxic lymphocyte function, mainly that of natural killer (NK) cells. Our understanding of NK cell function deficiency in patients with CHS and how LYST regulates lytic granule exocytosis is very limited. OBJECTIVE: We sought to delineate cellular defects associated with LYST mutations responsible for the impaired NK cell function seen in patients with CHS. METHODS: We analyzed NK cells from patients with CHS with missense mutations in the LYST ARM/HEAT (armadillo/huntingtin, elongation factor 3, protein phosphatase 2A, and the yeast kinase TOR1) or BEACH (beige and Chediak-Higashi) domains. RESULTS: NK cells from patients with CHS displayed severely reduced cytotoxicity. Mutations in the ARM/HEAT domain led to a reduced number of perforin-containing granules, which were significantly increased in size but able to polarize to the immunologic synapse; however, they were unable to properly fuse with the plasma membrane. Mutations in the BEACH domain resulted in formation of normal or slightly enlarged granules that had markedly impaired polarization to the IS but could be exocytosed on reaching the immunologic synapse. Perforin-containing granules in NK cells from patients with CHS did not acquire certain lysosomal markers (lysosome-associated membrane protein 1/2) but were positive for markers of transport vesicles (cation-independent mannose 6-phosphate receptor), late endosomes (Ras-associated binding protein 27a), and, to some extent, early endosomes (early endosome antigen 1), indicating a lack of integrity in the endolysosomal compartments. NK cells from patients with CHS had normal cytokine compartments and cytokine secretion. CONCLUSION: LYST is involved in regulation of multiple aspects of NK cell lytic activity, ranging from governance of lytic granule size to control of their polarization and exocytosis, as well as regulation of endolysosomal compartment identity. LYST functions in the regulated exocytosis but not in the constitutive secretion pathway.

Towards the targeted management of Chediak-Higashi syndrome.

Chediak-Higashi syndrome (CHS) is a rare, autosomal recessive congenital immunodeficiency caused by mutations in CHS1, a gene encoding a putative lysosomal trafficking protein. In the majority of patients, this disorder is typically characterized by infantile-onset hemophagocytic lymphohistiocytosis (HLH), which is lethal unless allogeneic transplantation is performed. A small number of individuals have the attenuated form of the disease and do not benefit from transplant. Improved outcomes of transplantation have been reported when performed before the development of HLH, thus it is important to quickly differentiate patients that present with the childhood form of disease and to prematurely enroll them into a transplantation protocol. In addition, this would also preclude those that exhibit clinical phenotypes of adolescent and adult CHS from this treatment. Patients with an absence of cytotoxic T lymphocyte (CTL) function have a high risk for developing HLH, and could therefore benefit the most from early hematopoietic stem cell transplantation (HSCT). However, although normal CTL cytotoxicity or bi-allelic missense mutations do not exclude the occurrence of HLH in childhood, a more conservative approach is justified. This article summarizes recent advances in the clinical characterization of CHS patients, provides updates on promising new testing methods, and focuses on specific therapeutic approaches.

Change in visual acuity in albinism in the early school years.

PURPOSE: To determine whether binocular best-corrected visual acuity (B-BCVA) improves in the early school years in patients with albinism and whether this is related to type of albinism, ocular pigment, or appearance of the macula. METHODS: Patients with albinism seen between 5.5 and 9 years (Visit A) and 9.5 and 14 years of age (Visit B), with visits separated by at least 2.5 years, were included. Type of albinism, B-BCVA, glasses wear, iris pigment and macular transparency grade, and presence or absence of an annular reflex and melanin in the macula were recorded. RESULTS: Mean B-BCVA was 20/84 at Visit A and 20/61 at Visit B (P < .001). B-BCVA improved in 80%. Improvement in B-BCVA and glasses wear, iris grade, macular grade, macular melanin, and annular reflex were weakly correlated. However, a moderate correlation was found between measured B-BCVA and iris grade at Visit A (r = 0.485, P < .001) and Visit B (r = 0.467, P < .001), and the presence of macular melanin at Visit A (r = 0.436, P < .001) and Visit B (r = 0.482, P < .001). CONCLUSIONS: B-BCVA often improves in albinism in the early school years and this observation should be included in counseling. The etiology is unknown but may be related to change in nystagmus, use of precise null point, developmental maturation, and/or some of the ocular characteristics evaluated in this study.

The regulated secretory pathway in CD4(+) T cells contributes to human immunodeficiency virus type-1 cell-to-cell spread at the virological synapse.

Direct cell-cell spread of Human Immunodeficiency Virus type-1 (HIV-1) at the virological synapse (VS) is an efficient mode of dissemination between CD4(+) T cells but the mechanisms by which HIV-1 proteins are directed towards intercellular contacts is unclear. We have used confocal microscopy and electron tomography coupled with functional virology and cell biology of primary CD4(+) T cells from normal individuals and patients with Chediak-Higashi Syndrome and report that the HIV-1 VS displays a regulated secretion phenotype that shares features with polarized secretion at the T cell immunological synapse (IS). Cell-cell contact at the VS re-orientates the microtubule organizing center (MTOC) and organelles within the HIV-1-infected T cell towards the engaged target T cell, concomitant with polarization of viral proteins. Directed secretion of proteins at the T cell IS requires specialized organelles termed secretory lysosomes (SL) and we show that the HIV-1 envelope glycoprotein (Env) localizes with CTLA-4 and FasL in SL-related compartments and at the VS. Finally, CD4(+) T cells that are disabled for regulated secretion are less able to support productive cell-to-cell HIV-1 spread. We propose that HIV-1 hijacks the regulated secretory pathway of CD4(+) T cells to enhance its dissemination.

Rituximab and cyclosporine therapy for accelerated phase Chediak-Higashi syndrome.

A 19-month-old male with Chediak-Higashi syndrome developed Epstein-Barr virus (EBV)-associated accelerated phase. Real-time polymerase chain reaction showed high EBV-DNA levels in plasma and peripheral blood mononuclear cells. His condition was refractory to conventional treatments for hemophagocytic lymphohistiocytosis, including corticosteroids, cyclosporine, and etoposide. In situ hybridization revealed higher proportion of EBER-1-positive cells in CD19+ cell fraction than in CD8+ cell fraction. Complete remission was achieved by combination therapy with rituximab and cyclosporine; subsequent bone marrow transplantation was successful. Combination therapy with rituximab and cyclosporine could be effective in patients with EBV-infected T and B cells.

Accelerated phase of chediak higashi syndrome mimicking lymphoma--a case report.

SUMMARY: Chediak Higashi Syndrome (CHS) is a rare autosomal recessive disease, characterized by partial oculocutaneous albinism, frequent pyogenic infections, and the presence of abnormal large granules in leukocytes and other granule containing cells. The abnormal granules are readily seen in blood and marrow granulocytes. About 50% to 85% of patients eventually enter an accelerated phase, manifested by fever, lymphadenopathy, anemia, jaundice, neutropenia, thrombocytopenia, and widespread lymphohistiocytic organ infiltrates. The first accelerated phase of CHS may occur shortly after birth or several years later. Most patients undergo a variable period of recurrent infections before going into the accelerated phase. Therefore, primary presentation in the accelerated phase is unusual. This case was referred to our institution that is a tertiary care cancer centre, with a clinical diagnosis of lymphoma/leukemia. Hence this interesting case of CHS in accelerated phase at presentation is described. The child had 1-month history of fever, bilateral neck swellings, and loss of appetite. On the basis of the clinical presentation, hematologic, and histopathologic findings, a diagnosis of accelerated phase of CHS was made. The child was treated with antipyretics, antibiotics, and stem cell transplantation was suggested to him. When the child presents to a hospital with oculocutaneous albinism and recurrent infections, careful examination of the peripheral blood smear by an experienced morphologist cannot be overemphasized. A high degree of awareness and early recognition of the syndrome, could lead to the institution of the only possible curative treatment, bone marrow transplant, before the accelerated phase supervenes.

Regulating secretory lysosomes.

Secretory lysosomes are lysosomes which are capable of undergoing regulated secretion in response to external stimuli. Many cells of the immune system use secretory lysosomes to release proteins involved in their specialised effector mechanisms. Precisely how lysosomal secretion is regulated in each of these cell types is now the study of much research as these mechanisms control the ability of each of these cells to function. Studies on a number of human genetic diseases have identified some key proteins in controlling secretory lysosome release, and now many interacting partners have been identified. The different regulatory components seem to vary from one cell type to another, providing a multitude of ways for fine tuning the release of secretory lysosomes.

Chediak-Higashi syndrome with parkinsonism.

Chediak-Higashi syndrome (CHS), typically presents with partial albinism and severe hematological abnormalities. About 10% of the patients have a mild adult form associated with various neurological manifestations. We describe the case of a 24-year-old woman with parkinsonism that responded well to antiparkinsonian drugs.

Chediak-Higashi syndrome: a case report.

A 5-month-old Chinese male infant was referred to the University Hospital, Kuala Lumpur for persistent fever, generalised rash and abdominal distension. Clinically he was suspected to have haemophagocytic lymphohistiocytosis. Haematological findings including the presence of several abnormal giant granules in neutrophils and single large azurophilic granules in many lymphocytes and monocytes in the peripheral blood established the diagnosis of Chediak-Higashi syndrome. The patient responded to allogeneic bone marrow transplant. This paper discusses the characteristic features, clinical course and management of this rare disorder. We suggest that peripheral blood film examination for the abnormal giant granules in granulocytes is an essential investigation in all young children with frequent recurrent infections or who are suspected to have virus-associated haemophagocytic syndrome or familial haemophagocytic lymphohistiocytosis.

Chediak-Higashi syndrome: four cases from Northern Finland.

UNLABELLED: Chediak-Higashi syndrome (CHS) is a rare multiorgan disease entity with autosomal recessive inheritance characterized by oculocutaneous albinism, bleeding tendency, recurrent bacterial infections and various neurological symptoms. Intracellular vesicle formation is deficient, resulting in giant granules in many cells, e.g. giant melanosomes in the melanocytes. Diagnosis has been based on morphological examination of peripheral blood and bone marrow, with giant granules seen in cells of the myeloid lineage and in lymphocytes. The ultimate diagnostic test is to look for a mutated LYST gene. Most patients develop an accelerated phase of the disease with deposition of lymphohistiocytes in the liver, spleen, lymph nodes and bone marrow, resulting in hepatosplenomegaly, bone marrow infiltration and haemophagocytosis. Peripheral blood neutropenia becomes more profound as anaemia and thrombocytopenia develop. Most patients succumb before the age of 10 years. Four patients with CHS are described, one of whom is a long-term survivor after successful allogeneic bone marrow transplantation, two succumbed during the accelerated phase and one is living with a chronic form of the disease. CONCLUSION: Allogeneic bone marrow transplantation from an HLA-matched sibling is the therapy of choice and should be performed early. If there is no matched family donor, an unrelated donor or a placental blood graft is a good alternative. The clinical picture of CHS is heterogeneous and therapeutic decisions need to be made on an individual basis.

Platelet dysfunction in Chediak-Higashi syndrome-affected cattle.

A serious symptom of cattle affected with Chediak-Higashi syndrome (CHS) is a bleeding tendency. This diathesis is characterized by insufficient platelet aggregation as a result of depressed response to collagen. One possible cause for the depression is a decrease in contribution of endogenous agonists such as ADP or thromboxane A(2), which are released following collagen stimulation. However, these endogenous agonists play only a minor role in collagen-induced aggregation of bovine platelets. More importantly, activation of phospholipase C as a result of a direct action of collagen is depressed, leading to a depression of Ca(2+) mobilization, in platelets from CHS-affected cattle. Several types of collagen receptor are proposed to work in concert to induce aggregation. Among them, glycoprotein VI (GPVI) and GPIa/IIa (integrin alpha2 beta1) have been supposed to play dominant roles in collagen-induced aggregation. However, there are arguments about the role of each receptor, especially the role of GPIa/IIa, and the crosstalk between receptors. Recently, we reported that the Ca(2+) signaling produced by rhodocytin, which had been first reported to be an agonist for the collagen receptor GPIa/IIa, produced much less Ca(2+) signaling in CHS platelets than in normal ones, whereas that produced by GPVI activators was normal. These suggest that GPIa/IIa or the rhodocytin-associated pathway is impaired in CHS platelets. CHS platelets are valuable to reassess the mechanism of collagen-dependent signal transduction system and to delineate the inter-relationship among collagen receptors.

Cardiac failure in an infant with Chediak-Higashi syndrome: a hypothesis of the effect of diadenosine polyphosphates.

A 14-week-old boy with undiagnosed Chediak-Higashi syndrome developed fever with a high temperature and acute cardiac failure after having received a scheduled vaccination. We hypothesize that decreased concentrations and receptor binding of serum and tissue diadenosine polyphosphates, such as AP4A, AP5A, or AP6A, which are stored in various tissues and serve as extra-cellular signaling molecules or are secreted by cells in response to physiologically stressful stimuli, lead to the observed severe tachyarrhythmia. Diadenosine polyphosphates normally have a negative chronotropic and inotropic effect. This is the first report of severe cardiac failure in a child with Chediak-Higashi syndrome and we suggest that cardiac arrhythmias should be considered in such children in the event of high fever. Our hypothesis requires further investigation in other patients.