Hematopoietic stem cell transplantation in severe congenital neutropenia.

BACKGROUND: Severe congenital neutropenia (SCN) is an immunodeficiency characterized by disturbed myelopoiesis and an absolute neutrophil count (ANC) <0.5 × 10(9)/L. SCN is also a premalignant condition; a significant proportion of patients develop myelodysplastic syndrome or leukemia (MDS/L). Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for SCN. PROCEDURE: Since 2004, eight HSCT have been performed in seven patients at our center. The indications were transformation to MDS/L (n = 2), granulocyte colony-stimulating factor receptor (CSF3R) mutation(s) (n = 2), granulocyte colony-stimulating factor (G-CSF) resistance (n = 2), and at the patient's own request (n = 1). RESULTS: The mean age at transplantation was 13 years (2.8-28 years) (mean follow-up 32 months, range 21-60). Three patients harbored ELANE mutations, three HAX1 mutations, and in one patient no causative mutation was identified. Two of the ELANE mutations were novel mutations. Three patients initially received myeloablative conditioning and four had reduced intensity conditioning (RIC). Three grafts were from HLA-identical siblings, three from matched unrelated donors and two were cord blood units. Engraftment occurred in all patients. Two of seven (29%) patients died; both had MDS/L and both were among the three that underwent myeloablative conditioning. One patient has chronic GVHD 2 years post-transplant. CONCLUSIONS: The role of HSCT should be explored further in patients with SCN. In particular, the influence of the conditioning regime needs to be evaluated in a larger cohort of patients.

Hematopoietic stem cell transplantation in children with cancer and the risk of long-term psychological morbidity in the bereaved parents.

We have investigated whether hematopoietic stem cell transplantation (HSCT) before the death of children with cancer has a long-term effect on the physical and psychological well-being of the parents. A nationwide questionnaire was sent out to all bereaved parents in Sweden who had lost a child due to a malignancy from 1992 to 1997. Self-reported levels of anxiety, depression and quality of life as well as overall psychological and physical well-being in bereaved parents of children who underwent HSCT were compared with bereaved parents whose children did not receive a transplant. Bereaved parents whose children underwent HSCT had, according to a visual digital scale, an increased relative risk (RR) of long-term anxiety (RR 1.5; 95% confidence interval (CI) 1.0-2.1), poor psychological well-being (RR1.3; 95% CI 1.1-1.5), low quality of life (RR 1.4; 95% CI 1.2-1.7) and poor physical health (RR 1.3; 95% CI 1.1-1.5), whereas the State-Trait Anxiety Inventory and 'The Göteborg Quality of Life Instrument' were non-significantly increased (RR 1.3; 95% CI 0.8-2.3 and RR 1.7; 95% CI 0.9-3.3, respectively). The risks of these consequences were further augmented in case of multiple HSCT. We suggest that bereaved parents of children undergoing HSCT may be at greater risk of decreased psychological well-being than other bereaved parents of children with cancer.

Central nervous system involvement in severe congenital neutropenia: neurological and neuropsychological abnormalities associated with specific HAX1 mutations.

OBJECTIVES: Homozygous mutations in the HAX1 gene were recently identified in severe congenital neutropenia patients belonging to the original Kostmann family in northern Sweden. Our observations suggested that these patients also develop neurological and neuropsychological symptoms. METHODS: Detailed clinical studies and mutation analyses were performed in the surviving patients belonging to the Kostmann kindred and in two patients not related to this family, along with studies of HAX1 splice variant expression in normal human tissues. RESULTS: Five of six Kostmann family patients and one other patient from northern Sweden harboured homozygous HAX1 mutations (568C-->T, Q190X) and one carried a heterozygous ELA2 gene mutation. One Swedish patient of Kurdish extraction carried alternative homozygous HAX1 mutations (131G-->A, W44X). All the three patients with Q190X mutations who were alive and available for evaluation developed neurological disease with decreased cognitive function, and three of four patients who reached 10 years developed epilepsy. In contrast, the patients with the ELA2 and W44X HAX1 mutations, respectively, showed no obvious neurological abnormalities. Moreover, two alternative HAX1 splice variants were identified in normal human tissues, including the brain. Both transcripts contained exon 5, harbouring the Q190X mutation, whereas the 5' end of exon 2 containing the W44X mutation was spliced out from the second transcript. CONCLUSIONS: We describe neurological and neuropsychological abnormalities for the first time in Kostmann disease patients. These central nervous system symptoms appear to be associated with specific HAX1 mutations.

Spectrum, and clinical and functional implications of UNC13D mutations in familial haemophagocytic lymphohistiocytosis.

OBJECTIVE: Familial haemophagocytic lymphohistiocytosis (FHL) is a fatal disorder of immune dysregulation with defective cytotoxic lymphocyte function. Disease-causing mutations have been identified in the genes encoding perforin (PRF1), syntaxin-11 (STX11), and Munc13-4 (UNC13D). We screened for UNC13D mutations and studied clinical and functional implications of such mutations in a well defined patient cohort. METHODS: Sequencing of UNC13D was performed in 38 FHL patients from 34 FHL families in which PRF1 and STX11 mutations had been excluded. RESULTS: We identified six different mutations affecting altogether 9/38 individuals (24%) in 6/34 (18%) unrelated PRF1/STX11-negative families. Four novel mutations were revealed; two homozygous nonsense mutations (R83X and W382X), one splice mutation (exon 28), and one missense mutation (R928P). In addition, two known mutations were identified (R214X and a deletion resulting in a frame-shift starting at codon 782). There was considerable variation in the age at diagnosis, ranging from time of birth to 14 years (median 69 days). Three of nine patients (33%) developed central nervous system (CNS) symptoms. Natural killer (NK) cell activity was impaired in all four patients studied. Defective cytotoxic lymphocyte degranulation was evident in the two patients investigated, more pronounced in the patient with onset during infancy than in the patient with adolescent onset. CONCLUSIONS: Biallelic UNC13D mutations were found in 18% of the PRF1/STX11-negative FHL families. Impairment of NK cell degranulation was less pronounced in a patient with adolescent onset. FHL should be considered not only in infants but also in adolescents, and possibly young adults, presenting with fever, splenomegaly, cytopenia, hyperferritinaemia, and/or CNS symptoms.

Genotype-phenotype study of familial haemophagocytic lymphohistiocytosis due to perforin mutations.

BACKGROUND: PRF1 gene mutations are associated with familial haemophagocytic lymphohistiocytosis type 2 (FHL2). Genotype-phenotype analysis, previously hampered by limited numbers of patients, was for the first time performed by data pooling from five large centres worldwide. PATIENTS AND METHODS: Members of the Histiocyte Society were asked to report cases of FHL2 on specific forms. Data were pooled in a common database and analysed. RESULTS: The 124 patients had 63 different mutations (including 15 novel mutations): 11 nonsense, 10 frameshift, 38 missense and 4 in-frame deletions. Some mutations were found more commonly: 1122 G-->A (W374X), associated with Turkish origin, in 32 patients; 50delT (L17fsX22) associated with African/African American origin, in 21 patients; and 1090-91delCT (L364fsX), in 7 Japanese patients. Flow cytometry showed that perforin expression was absent in 40, reduced in 6 and normal in 4 patients. Patients presented at a median age of 3 months (quartiles: 2, 3 and 13 months), always with fever, splenomegaly and thrombocytopenia. NK activity was absent in 36 (51%), 5% in 4 (6%), "reduced" in 2 (3%) (not reported, n = 54). Nonsense mutations were significantly associated with younger age at onset (p<0.001) and absent natural killer activity (p = 0.008). CONCLUSION: PRF1 mutations are spread over the functional domains. Specific mutations are strongly associated with Turkish, African American and Japanese ethnic groups. Later onset and residual cytotoxic function are observed in patients with at least one missense mutation.

Assignment of the gene locus for severe congenital neutropenia to chromosome 1q22 in the original Kostmann family from Northern Sweden.

Autosomal recessive severe congenital neutropenia (SCN) or Kostmann syndrome is characterised by reduced neutrophil counts and subsequent recurrent bacterial infections. The disease was originally described in a large consanguineous pedigree from Northern Sweden. A genome-wide autozygosity scan was initiated on samples from four individuals in the original pedigree using high density single nucleotide polymorphism (SNP) genotyping arrays in order to map the disease locus. Thirty candidate regions were identified and the ascertainment of samples from two additional patients confirmed a single haplotype with significant association to the disorder (p<0.01) on chromosome 1q22. One affected individual from the original Kostmann pedigree was confirmed as a phenocopy. The minimal haplotype shared by affected individuals spans a candidate region of 1.2 Mb, containing several potential candidate genes.

A journey of hope: lessons learned from studies on rare diseases and orphan drugs.

Rare diseases are frequently life-threatening or chronically debilitating and the impact on the quality of life of affected patients and their family members is thus significant. However, drug development for these conditions has been limited by a lack of understanding of the underlying mechanisms of disease and the relative unavailability of subjects for clinical trials, as well as the prohibitive cost of investing in a novel pharmaceutical agent with poor market potential. Nevertheless, the introduction of Orphan Drug legislations has provided important incentives for the development of orphan drugs (i.e. drugs that have been abandoned or 'orphaned' by major drug companies). Moreover, recent studies on rare diseases, including inherited immunodeficiencies and metabolic disorders, have served not only to alleviate the plight of patients with rare diseases, but also yielded valuable information on biological processes of relevance for other, more common conditions. These lessons, along with the crucial importance of cooperation between academic institutions, pharmaceutical companies, patient advocacy groups and society in the elucidation of rare diseases, are highlighted in the present review.

Spectrum and clinical implications of syntaxin 11 gene mutations in familial haemophagocytic lymphohistiocytosis: association with disease-free remissions and haematopoietic malignancies.

OBJECTIVE: To determine the frequency and spectrum of mutations in the gene encoding syntaxin 11 (STX11) in familial haemophagocytic lymphohistiocytosis (FHL), a rare autosomal recessive disorder of immune dysregulation characterised by a defect in natural killer cell function. METHODS: Mutational analysis of STX11 by direct sequencing was done in 28 FHL families that did not harbour perforin mutations, previously identified in some FHL patients. A detailed investigation of clinical features of these patients was also undertaken. RESULTS: Two different STX11 mutations were identified, one nonsense mutation and one deletion, affecting six of 34 children in four of 28 unrelated PRF1 negative families. Both mutations have been reported before. Three patients experienced long periods (> or = 1 year) in remission without specific treatment, which is very uncommon in this disease. Despite the milder phenotype, some children with STX11 mutations developed severe psychomotor retardation. Two of the six patients harbouring STX11 gene defects developed myelodysplastic syndrome (MDS) or acute myelogenous leukaemia (AML). CONCLUSIONS: STX11 gene mutations were found in 14% of the PRF1 negative FHL families included in the present cohort. These results suggest that STX11 gene mutations may be associated with secondary malignancies (MDS/AML), and that there is segregation of specific clinical features in FHL patients with an underlying genotype.

Risk factors for diabetes insipidus in langerhans cell histiocytosis.

BACKGROUND: Diabetes insipidus (DI) is the most frequent central nervous system (CNS)-related permanent consequence in Langerhans cell histiocytosis (LCH), which mostly requires life-long hormone replacement therapy. In an attempt to define the population at risk for DI, 1,741 patients with LCH registered on the trials DALHX 83 and DALHX 90, LCH I and LCH II were studied. RESULTS: Overall 212 of 1,741 patients (12%) was reported to have DI. In 102 of 1,741 patients (6%) DI was present at diagnosis of LCH. One thousand one hundred eighty three of 1,539 patients without DI at diagnosis had follow up information. One hundred ten of these (9%) later developed DI. The risk of developing DI was 20% at 15 years after diagnosis. Multisystem disease patients at diagnosis carried a 4.6-fold risk for DI compared to single system patients. Craniofacial lesions, in particular in the "ear," "eye," and oral region were associated with a significantly increased risk for DI (relative hazard rate, RHR 1.7), independent of the extent of disease. No influence of the duration of therapy could be determined, but the duration of initial disease activity (RHR 1.5) and the occurrence of reactivations (RHR 3.5) significantly increased the risk for DI. CONCLUSIONS: Patients with multisystem disease and craniofacial involvement at diagnosis, in particular of the "ear," "eye," and the oral region carry a significantly increased risk to develop DI during their course. This risk is augmented when the disease remains active for a longer period or reactivates.

Findings in familial haemophagocytic lymphohistiocytosis prior to symptomatic presentation.

UNLABELLED: Familial haemophagocytic lymphohistiocytosis (FHL) is a rare, autosomal recessive disease of infancy and early childhood clinically characterized by fever, hepatosplenomegaly, lymphadenopathy, rash, neurological symptoms and icterus. Common laboratory findings include cytopenia, elevated liver enzymes, hyperbiliriubinaemia, hypofibrinogenaemia and hypertriglyceridaemia. The natural killer cell function is frequently decreased or absent. A diffuse lymphohistiocytic infiltration is seen in the reticuloendothelial system, often with haemophagocytosis. Molecular diagnosis is available in a minority of FHL families. Without adequate treatment and bone-marrow transplantation, the disease is fatal. A 6-wk-old child with FHL is presented. Shortly before the clinical onset of the disease, blood testing and bone-marrow examination had been carried out. All results were considered normal at that time. CONCLUSION: Blood tests and bone-marrow examination may be normal shortly before the clinical presentation and therefore do not exclude the diagnosis of FHL. There is a need for extended molecular diagnostic possibilities.

Familial hemophagocytic lymphohistiocytosis: too little cell death can seriously damage your health.

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare and fatal disease of early childhood characterized by a non-malignant accumulation of activated T lymphocytes and histiocytes in the reticuloendothelial system. Moreover, immune system derangement, with prominent hypercytokinemia and low or absent cytotoxic T and natural killer (NK) cell activity, is a consistent feature of this autosomal recessive disorder. Recent work has demonstrated that the degree of spontaneous caspase activation in FHL lymphocytes is attenuated in vitro whereas Fas-mediated caspase activation and apoptosis induction remains unmitigated, and FHL can thus be distinguished from the related chronic disorder of immune regulation termed autoimmune lymphoproliferative syndrome or ALPS. However, subsequent studies have identified mutations in the gene encoding perforin, a cytotoxic granule constituent required for apoptotic killing of target cells, in a number of FHL patients. Hence, the underlying defect in FHL may be conceived of as a lack of apoptosis triggering within the immune system, rather than apoptosis resistance per se. These observations represent an important step in our understanding of the pathogenesis of FHL and also serve to emphasize the pivotal role of cellular (perforin-based) cytotoxicity in the regulation of immune homeostasis.

Pulmonary abnormalities at long-term follow-up of patients with Langerhans cell histiocytosis.

BACKGROUND: In Langerhans cell histiocytosis (LCH) pulmonary involvement, which is often initially asymptomatic, may contribute to significant morbidity and mortality. To determine the long-term prognosis, a cross-sectional study was undertaken. PROCEDURE: Forty-one patients with > or = 5 years follow-up after the diagnosis of LCH were interviewed and underwent physical examination, blood tests, a chest X-ray and a high-resolution CT (HRCT) of the lungs. All patients included had been referred to the Department of Pediatrics at the Karolinska Hospital in Stockholm between July 1962 and February 1990 (median follow-up 16 years). Biopsies from all patients were reviewed and confirmed to be consistent with LCH. Information on previous clinical features including treatment and the results of chest X-rays were also collected for risk factor analysis. RESULTS: Radiographic abnormalities of the lungs (cysts and/or emphysema), found in 10/41 (24%) at follow-up, were classified into five groups according to the extent of the cysts. These patients had more often suffered from multisystem than from single-system disease (P = 0.01), were significantly older at diagnosis (P < 0.001), and had been more heavily treated with chemotherapy and/or radiotherapy. They were also more frequently smokers (P < 0.0001) and 7/10 (70%) had suffered lung involvement at diagnosis. At the time of diagnosis of the pulmonary involvement, 4/10 (40%) patients had respiratory symptoms, but only 2/10 (20%) had symptoms at follow-up. CONCLUSIONS: Ten (24%) of the 41 patients had abnormal findings on radiological examination of the lungs at long-term follow-up and seven are or had been smokers. It is of great importance that patients with LCH be informed about smoking-related pulmonary morbidity. Prolonged monitoring of the lungs for smokers and patients with known pulmonary involvement is recommended.

Smoking preceded pulmonary involvement in adults with Langerhans cell histiocytosis diagnosed in childhood.

Two patients with childhood Langerhans cell histiocytosis (LCH) (aged 2 and 6 y at diagnosis) in whom pulmonary involvement was diagnosed in adulthood, 23 and 12 y later, respectively, are presented. In each patient, smoking preceded the diagnosis of pulmonary involvement by 3 y, providing further evidence that smoking is a risk factor in the development of pulmonary LCH.

Detection of Langerhans cell histiocytosis lesions with somatostatin analogue scintigraphy--a preliminary report.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a disease where granulomatous lesions occur in various organs of the body. The etiology and pathogenesis remain unknown. Inflammatory destructive activity give rise to a wide range of clinical symptoms, including fractures, skin lesions, pulmonary fibrosis, endocrinopathies, and central nervous system deterioration. Since disease activity may ultimately lead to fibrosis and organ damage, it is important to have diagnostic tools to detect disease activity early. PROCEDURE: The present study was undertaken in order to evaluate whether somatostatin analogue scintigraphy ((111)In-pentetreotide or OctreoScan could be used in detecting LCH granulomas and to compare this method with the radiologic methods used today in LCH diagnosis and follow-up. The somatostatin analogue octreotide used here binds to the cell membrane of activated lymphocytes expressing somatostatin receptors. RESULTS: In five out of six children studied, LCH lesions detected by other means were also detected with (111)In-pentetreotide. It can be speculated that the lesion in the remaining patient was not active at the time of investigation. In addition, in two of the patients signs of disease activity not previously known were revealed. CONCLUSION: (111)In-pentetreotide can be used to detect active LCH lesions. Since the biologically active somatostatin analogue decreases inflammatory activity, this may also be of therapeutic value in selected patients with LCH. More studies are needed to evaluate the diagnostic and potential therapeutic usefulness of this radionuclide.

[Parvovirus B19 infection--an incidious chameleon]. / Parvovirus B19-infektion--en lömsk kameleont.

Parvovirus B19 is a common source of infection with a seroprevalence of 60-70 per cent in the adult population. The most common manifestation is erythema infectiosum ("fifth disease"), with exanthem, fever and upper airway symptoms in children. The infection can give rise to a multifaceted clinical picture and is probably underdiagnosed, particularly in risk groups (individuals with haemolytic anaemia or immunosuppression, and fetuses). Serological diagnosis can now be complemented with the demonstration of viral DNA using the PCR (polymerase chain reaction) test in various body fluids, or tissue biopsy. Recent years have witnessed manifest increase in clinical knowledge of parvovirus B19-associated complications, and their diagnosis and treatment.

[Apoptosis required for maintenance of homeostasis: familial hemophagocytic lymphohistiocytosis caused by too little cell death]. / Lagom är bäst även när det gäller apoptos. Brist på apoptos orsak till familjär hemofagocyterande lymfohistiocytos.

Apoptosis or programmed cell death is essential for the maintenance of tissue homeostasis. Recent studies have implicated the dysregulation of apoptosis in a plethora of human diseases. Hence, perturbation of the death program intrinsic to every cell may result in essentially too little or too much apoptosis, which may in turn lead to proliferative or degenerative diseases respectively. In the present review, we discuss our current molecular understanding of the apoptotic process and its possible role in human disease, with particular emphasis on the rare and invariably fatal disease of early childhood, termed familial hemophagocytic lymphohistiocytosis, in which mutations in the perforin gene were recently identified.