Pulmonary interstitial glycogenosis - A systematic analysis of new cases.

BACKGROUND: Pulmonary interstitial glycogenosis (PIG) is a rare paediatric interstitial lung disease of unknown cause. The diagnosis can only be made by lung biopsy. Less than 100 cases have been reported. Clinical features, treatment and outcomes have rarely been assessed systematically in decent cohorts of patients. METHODS: In this retrospective multicentre study, the clinical presentation, radiologic findings, pattern of lung biopsy, extrapulmonary comorbidities, treatment and outcome of eleven children with PIG were collected systematically. RESULTS: 10/11 children presented with respiratory distress immediatly after birth and 8/11 needed invasive ventilation. In 8/11 children extrapulmonary comorbidities were present, congenital heart defects being the most common. 7/11 children received systemic glucocorticoids and of these four showed a clear favorable response. During a median follow-up of 3.0 years (range 0.42-12.0) one child died, while 10 patients improved. Chest CT-scans showed ground-glass opacities (7/10), consolidations (6/10), linear opacities (5/10) and mosaic attenuation (4/10) without uniform pattern. Besides interstitial thickening related to undifferentiated glycogen positive mesenchymal cells all tissue samples showed growth abnormalities with reduced alveolarization. CONCLUSIONS: PIG is associated with alveolar growth abnormalities and has to be considered in all newborns with unexplained respiratory distress. Apparent treatment benefit of glucocorticosteroids needs to be evaluated systematically.

Niemann-Pick Type C-2 Disease: Identification by Analysis of Plasma Cholestane-3ß,5α,6ß-Triol and Further Insight into the Clinical Phenotype.

INTRODUCTION: Niemann-Pick type C disease is a rare disorder caused by impaired intracellular lipid transport due to mutations in either the NPC1 or the NPC2 gene. Ninety-five % of NPC patients show mutations in the NPC1 gene. A much smaller number of patients suffer from NPC2 disease and present respiratory failure as one of the most frequent symptoms. Several plasma oxysterols are highly elevated in NPC1 and can be used as a biomarker in the diagnosis of NPC1. METHODS: Plasma cholestane-3ß,5α,6ß-triol was evaluated as biomarker for NPC2 by GC/MS and LC-MS/MS analysis. The diagnosis was confirmed by Sanger sequencing and filipin staining. RESULTS: We report three NPC2 patients with typical respiratory problems and a detailed description of the nature of the lung disease in one of them. All patients had elevated levels of plasma cholestane-3ß,5α,6ß-triol. In two of these patients, the positive oxysterol result led to a rapid diagnosis of NPC2 by genetic analysis. The phenotype of the third patient has been described previously. In this patient a cholestane-3ß,5α,6ß-triol concentration markedly above the reference range was found. CONCLUSIONS: Measurement of plasma cholestane-3ß,5α,6ß-triol enables to discriminate between controls and NPC1 and NPC2 patients, making it a valuable biomarker for the rapid diagnosis not only for NPC1 but also for NPC2 disease.The measurement of oxysterols should be well kept in mind in the differential diagnosis of lysosomal diseases, as the elevation of oxysterols in plasma may speed up the diagnosis of NPC1 and NPC2.

Neonatal respiratory insufficiency caused by an (homozygous) ABCA3-stop mutation: a systematic evaluation of therapeutic options.

BACKGROUND: Autosomal recessive ABCA3 (ATP-binding cassette protein A3) gene mutations have been associated with neonatal respiratory distress and pediatric interstitial lung disease. The clinical course of the disease depends on the underlying mutations. Therefore, knowledge of course, symptoms and treatment of the disease is important. PATIENT AND METHODS: A term newborn suffered from progressive respiratory insufficiency, which led to death at the age of 4.8 months. The girl developed interstitial lung disease. Infections as well as structural and functional disorders of the lung were systematically excluded. A homozygous c.4681C > T (Arg 1561 Stop) mutation of the ABCA3 gene was identified. A literature review of the pathophysiology and treatment options of the disease was done. Therapeutic approaches with corticosteroids, macrolide, and hydroxychloroquine did not improve the clinical course. RESULTS: Therapeutic strategies for chronic interstitial lung disease have been used successfully in cases of a mild clinical course in juvenile patients with ABCA3 gene mutation. In our patient with homozygous ABCA3 gene mutation,they were not effective. Lung transplantation remains as a therapeutic option, but because of donor organ shortage and associated morbidity and mortality it is rarely feasible. CONCLUSION: More experience in the treatment of newborns with ABCA3 gene mutations is needed. Randomized, prospective evaluation of the different therapeutic approaches in a specific registry may improve prognosis and treatment of affected individuals.

Successful treatment of neonatal respiratory failure caused by a novel surfactant protein C p.Cys121Gly mutation with hydroxychloroquine.

SFTPC (surfactant protein C) mutations resulting in SP-C deficiency causing ongoing respiratory failure in the neonatal period represent a rare entity. We report a full-term female infant who developed respiratory distress and respiratory failure shortly after birth. From the first day of life the infant was mechanically ventilated. Application of exogenous surfactant or cortisone did not lead to any clinical improvement. Genetic analysis identified a novel SFTPC mutation as the cause of her lung disease. The patient was diagnosed as heterozygous for a p.Cys121Gly/C121G substitution encoded by exon 4, which could not be detected in both parents. Experimental therapy with hydroxychloroquine resulted in a significant clinical improvement within 2 weeks time. Mechanical ventilation was no longer needed, and the patient was discharged without additional oxygen demand. The patient remained well under therapy till the age of 6 months. After that time, the therapy was successfully discontinued.

Ursodeoxycholic acid therapy in cystic fibrosis liver disease--a retrospective long-term follow-up case-control study.

BACKGROUND: The prevention and treatment of liver disease associated with cystic fibrosis remain a significant unresolved problem. AIM: To assess the long-term effects of continuous ursodeoxycholic acid (UDCA) therapy in cystic fibrosis patients with constantly elevated serum liver enzymes. METHODS: The primary endpoint was the incidence of overt liver disease. Between 1989 and 2005, UDCA treatment was started in 98 subjects from a cohort of 382 cystic fibrosis patients. These subjects were compared with a historic control group of 352 subjects who attended our centre between 1975 and 1989 before UDCA became standard treatment. For the long-term comparison of liver function and lung function tests, a group of 98 matched contemporary cystic fibrosis patients were compared with the 98 subjects treated with UDCA. RESULTS: Overt liver disease developed in only one of the 382 patients who was treated with UDCA for increased serum liver enzymes compared with nine patients in the historic control group (P < 0.05). Serum liver enzyme levels declined in most patients receiving UDCA treatment during the 17-year follow-up (87/98, P < 0.05). No difference was seen in lung function between subjects with cystic fibrosis-related liver disease and the matched controls. CONCLUSIONS: Regular and systematic screening for liver involvement enables early introduction of UDCA therapy in affected cystic fibrosis patients, reduces the development of severe liver disease and leads to a significant and persistent improvement in serum liver tests, without impairing long-term pulmonary outcome.

The role of matrix metalloproteinases in cystic fibrosis lung disease.

Significant airway remodelling is a major component of the increased morbidity and mortality observed in cystic fibrosis (CF) patients. These airways feature ongoing leukocytic inflammation and unrelenting bacterial infection. In contrast to acute bacterial pneumonia, CF infection is not cleared efficiently and the ensuing inflammatory response causes tissue damage. This structural damage is mainly a result of free proteolytic activity released by infiltrated neutrophils and macrophages. Major proteases in this disease are serine and matrix metalloproteases (MMPs). While the role of serine proteases, such as elastase, has been characterised in detail, there is emerging evidence that MMPs could play a key role in the pathogenesis of CF lung disease. This review summarises studies linking MMPs with CF lung disease and discusses the potential value of MMPs as future therapeutic targets in CF and other chronic lung diseases.

Respiratory distress syndrome due to a novel homozygous ABCA3 mutation in a term neonate.

The authors report, for the first time in the literature, a case of respiratory distress syndrome in a term baby due to homozygosity for a p.Trp308Arg/W308R substitution in the ATP-binding cassette transporter 3. The sequence was confirmed by genetic analysis of the baby and both parents. Management and long-term outcome of a patient carrying this novel genetic defect have not been reported in the literature before. Currently, lung transplant appears to be the only long-term survival option available, for which, our patient is being evaluated.

Rehabilitation Programs for Cystic Fibrosis - View from a CF Center.

BACKGROUND: Rehabilitation programs are comprehensive interventions which effectively improve the health status and reduce costs in chronic respiratory illnesses. Because patients with cystic fibrosis have been discouraged to participate for concerns of microbial cross infection, the efficacy of systematic rehabilitation is unknown for this group. METHODS: We retrospectively studied 142 cystic fibrosis patients aged 2-46 years who participated in rehabilitation programs taking place in Germany/Switzerland and in Israel, focusing on changes in lung function and weight. RESULTS: During 172 stays in 97 patients in Israel and 68 stays in 45 patients rehabilitating in Germany/Switzerland, overall lung function and weight improved. Outcome did not differ between Israel and German/Swiss sites. Interestingly, lung function improved during the initial phase of the stay, whereas weight gain was sustained throughout. The study uncovered gaps in reporting sufficient individual outcome information back to the admitting centre. CONCLUSIONS: Rehabilitation programs specified for cystic fibrosis patients need to be assessed prospectively to optimize treatment of this life limiting condition.

Novel method to process cystic fibrosis sputum for determination of oxidative state.

BACKGROUND: Induced sputum is the most commonly used method to analyze airway inflammation in cystic fibrosis (CF) patients ex vivo. Due to the complex matrix of the sample material, precise and reliable analysis of sputum constituents depends critically on preanalytical issues. OBJECTIVES: Here we compared the commonly used method for sputum processing by dithiothreitol (DTT) with a novel mechanical method in regard to basal cellular parameters, neutrophil markers and glutathione (GSH) levels. METHODS: Sputum samples from CF patients were processed in parallel with or without the use of DTT. The key improvement of the mechanical method was the processing in many very small aliquots. Cellular and humoral markers were assessed and compared according to Bland-Altman. RESULTS: Total cell count, cell viability, differential cell count, neutrophil elastase levels and flow cytometrically analyzed neutrophil markers (CD63, CD11b, DHR) did not differ between the two methods. Intracellular and extracellular GSH levels were significantly higher in DTT-treated samples (p = 0.002). CONCLUSION: The mechanical sputum-processing method presented had a similar yield of cells and fluids as the conventional DTT method and the advantage of omitting the introduction of reducing agents. This method allows a more reliable analysis of redox-dependent airway inflammation in sputum cells and fluid from CF patients than methods utilizing DTT.

Respiratory disease in Niemann-Pick type C2 is caused by pulmonary alveolar proteinosis.

Niemann-Pick diseases are hereditary neurovisceral lysosomal lipid storage disorders, of which the rare type C2 almost uniformly presents with respiratory distress in early infancy. In the patient presented here, the NPC2 exon 4 frameshift mutation c.408_409delAA caused reduced NPC2 protein levels in serum and lung lavage fluid and the synthesis of an aberrant, larger sized protein of around 28 kDa. Protein expression was strongly reduced also in alveolar macrophages. The infant developed failure to thrive and tachypnea. Lung lavage, computer tomography, and histology showed typical signs of pulmonary alveolar proteinosis with an abnormal intraalveolar accumulation of surfactant as well as macrophages. An NPC2-hypomorph animal model also showed pulmonary alveolar proteinosis and accumulation of macrophages in the lung, liver, and spleen long before the mice died. Due to the elevation of cholesterol, the surfactant had an abnormal composition and function. Despite the removal of large amounts of surfactant from the lungs by therapeutic lung lavages, this treatment was only temporarily successful and the infant died of respiratory failure. Our data indicate that respiratory distress in NPC2 disease is associated with a loss of normal NPC2 protein expression in alveolar macrophages and the accumulation of functionally inactive surfactant rich in cholesterol.

[Cystic fibrosis care in transition from adolescence to adult age]. / Betreuung von Mukoviszidosepatienten beim Ubergang vom Jugendalter zum Erwachsenen.

During the last 30 years, life expectancy in patients with cystic fibrosis has significantly improved. In Germany, almost half of the 8500 patients are 18 years or older. Older patients have increased rates of cystic fibrosis typical complications, In addition the characteristic complications of adulthood, including arterial hypertension, hyperlipidemia, and cardiovascular diseases, occur. Also crisis of marriage or loss of work place, as well as family planning measures including in-vitro-fertilization are problems merely of the adult cystic fibrosis patient. Therefore adult patients should be treated in a centre specialized on adults. At the moment, in Germany only one third of all adult patients are followed up in an adult center, many patients are treated in age-independent centers, and also a significant number is treated in small clinics. In this article models for transition currently established in Germany are described and occurring problems with their implementation are discussed.

Innate immune receptors on neutrophils and their role in chronic lung disease.

Neutrophils, the prototypic cells of the innate immune system, are recruited to infected sites to protect the human body from invading pathogens. To accomplish this function, neutrophils sense pathogens and endogenous damage-associated molecules via innate immune receptors, such as Toll-like receptors (TLRs) and other pattern recognition receptors. This defence function is essential for the pulmonary microenvironment where the host is faced with millions of particles and pathogens inhaled daily. Chronic lung diseases, such as cystic fibrosis or chronic obstructive pulmonary disease are characterized by a neutrophil accumulation and chronic bacterial colonization of the airways. Consequently, insights into the role of TLRs on neutrophils in chronic lung diseases are of high relevance for further diagnostic and therapeutic approaches. Here we summarize and discuss recent advances in the expression, regulation and functional role of TLRs on neutrophils in chronic lung diseases.

Inhibition of airway proteases in cystic fibrosis lung disease.

Progressive lung disease determines the morbidity and mortality of cystic fibrosis (CF) patients. CF lung disease is characterised by endobronchial inflammation sustained by bacterial infections and an ongoing accumulation of airway neutrophils. Activated or necrotic neutrophils liberate proteases that cause damage to structural, cellular and soluble components of the pulmonary microenvironment. Among various proteases released by airway cells, elastase is considered to play the major role in CF lung disease. Based on this concept, several therapeutic approaches have been developed to inhibit free elastolytic activity, including small synthetic chemical compounds, semi-synthetic inhibitors and natural inhibitors of free elastase. The present review summarises and discusses the pathophysiological rationales, methodological requirements and clinical implications of inhibition of airway proteases in cystic fibrosis lung disease.

Surfactant protein B deficiency caused by a novel mutation involving multiple exons of the SP-B gene.

BACKGROUND: Inability to produce surfactant protein (SP)-B causes fatal neonatal respiratory disease. Homozygosity for a frameshift mutation (121ins2) in the gene encoding SP-B (SFTPB) is the predominant but not the exclusive cause of disease. OBJECTIVES: To report a novel mutation in the SFTB gene. METHODS: We analyzed tracheal aspirates, lung tissue obtained by in vivo lung biopsy and DNA from a newborn infant with lethal respiratory failure. RESULTS: DNA analysis revealed a large homozygous genomic deletion encompassing exon 7 and 8 of SFTPB gene, a mutation we described as c.673-1248del2959. The parents were both heterozygous carriers. Analysis of the SP profile in tracheal aspirates and lung tissue by immunohistochemistry, routine and electron microscopy supported the diagnosis of SP-B deficiency and suggested that this large mutation might lead to abnormal routing and processing of proSP-B and proSP-C. CONCLUSIONS: This report shows that SP-B deficiency can also be caused by a multi exon deletion in the SFTPB gene and this finding emphasizes the importance of using modern DNA analysis techniques capable of detecting multi exon deletions.

Children with absent surfactant protein D in bronchoalveolar lavage have more frequently pneumonia.

Surfactant protein D (SP-D) is an important component of the pulmonary host defense system. We hypothesized that bronchoalveolar lavage (BAL) SP-D levels are lower in children presenting with recurrent bronchitis, providing evidence for a role of SP-D in human respiratory diseases. SP-D levels in BAL were measured in 45 children, who suffered from recurrent bronchitis for an average of 2-3 yr. Clinical outcome was assessed 2 yr after BAL. For comparison, BAL fluids from 15 control children without respiratory symptoms were evaluated. Among the 45 children with recurrent bronchitis, 12 had no SP-D in their BAL at the time of investigation. These SP-D-deficient patients had more frequently pneumonias and their long-term outcome was worse than that of the children with detectable SP-D. No genetic cause could be identified for the SP-D deficiency. Among the children with recurrent bronchitis and SP-D clearly detectable in BAL, those with the diagnosis of allergic asthma had threefold elevated levels compared with controls. In accordance with animal and in vitro data, elevated SP-D concentrations in BAL may represent an up-regulation due to allergic airway inflammation. In contrast, SP-D deficiency due to consumption or failure to up-regulate SP-D may be linked to pulmonary morbidity in children.

Diversity of the basic defect of homozygous CFTR mutation genotypes in humans.

BACKGROUND: Knowledge of how CFTR mutations other than F508del translate into the basic defect in cystic fibrosis (CF) is scarce due to the low incidence of homozygous index cases. METHODS: 17 individuals who are homozygous for deletions, missense, stop or splice site mutations in the CFTR gene were investigated for clinical symptoms of CF and assessed in CFTR function by sweat test, nasal potential difference and intestinal current measurement. RESULTS: CFTR activity in sweat gland, upper airways and distal intestine was normal for homozygous carriers of G314E or L997F and in the range of F508del homozygotes for homozygous carriers of E92K, W1098L, R553X, R1162X, CFTRdele2(ins186) or CFTRdele2,3(21 kb). Homozygotes for M1101K, 1898+3 A-G or 3849+10 kb C-T were not consistent CF or non-CF in the three bioassays. 14 individuals exhibited some chloride conductance in the airways and/or in the intestine which was identified by the differential response to cAMP and DIDS as being caused by CFTR or at least two other chloride conductances. DISCUSSION: CFTR mutations may lead to unusual electrophysiological or clinical manifestations. In vivo and ex vivo functional assessment of CFTR function and in-depth clinical examination of the index cases are indicated to classify yet uncharacterised CFTR mutations as either disease-causing lesions, risk factors, modifiers or neutral variants.