[Pulmonary complications of Chronic Granulomatous Disease]

Chronic Granulomatosis Disease (CGD) is an inherited immune deficiency due to a mutation in the genes coding for the subunits of the NADPH oxidase enzyme that affects the oxidative capacity of phagocytic cells. It is characterized by increased susceptibility to bacterial and fungal infections, particularly Aspergillus, as well as complications associated with hyperinflammation and granulomatous tissue infiltration. There exist two types of frequently encountered pulmonary manifestations: (1) due to their being initially pauci-symptomatic, possibly life-threatening infectious complications are often discovered at a late stage. Though their incidence has decreased through systematic anti-bacterial and anti-fungal prophylaxis, they remain a major cause of morbidity and mortality; (2) inflammatory complications consist in persistent granulomatous mass or interstitial pneumoniae, eventually requiring immunosuppressive treatment. Pulmonary complications recurring since infancy generate parenchymal and bronchial sequelae that impact functional prognosis. Hematopoietic stem cell allograft is a curative treatment; it is arguably life-sustaining and may limit the morbidity of the disease. As a result of improved pediatric management, life expectancy has increased dramatically. That said, new challenges have appeared with regard to adults: difficulties of compliance, increased inflammatory manifestations, acquired resistance to anti-infectious therapies. These different developments underscore the importance of the transition period and the need for multidisciplinary management.

STAT3 mutation-associated airway epithelial defects in Job syndrome

BACKGROUND

Job syndrome is a disease of autosomal dominant hyper-IgE syndrome (AD-HIES). Patients harboring STAT3 mutation are particularly prone to airway remodeling and airway infections.

OBJECTIVES

Airway epithelial cells play a central role as the first line of defense against pathogenic infection and express high levels of STAT3. This study thus interrogates how AD-HIES STAT3 mutations impact the physiological functions of airway epithelial cells.

METHODS

This study created human airway basal cells expressing 4 common AD-HIES STAT3 mutants (R382W, V463del, V637M, and Y657S). In addition, primary airway epithelial cells were isolated from a patient with Job syndrome who was harboring a STAT3-S560del mutation and from mice harboring a STAT3-V463del mutation. Cell proliferation, differentiation, barrier function, bacterial elimination, and innate immune responses to pathogenic infection were quantitatively analyzed.

RESULTS

STAT3 mutations reduce STAT3 protein phosphorylation, nuclear translocation, transcription activity, and protein stability in airway basal cells. As a consequence, STAT3-mutated airway basal cells give rise to airway epithelial cells with abnormal cellular composition and loss of coordinated mucociliary clearance. Notably, AD-HIES STAT3 airway epithelial cells are defective in bacterial killing and fail to initiate vigorous proinflammatory responses and neutrophil transepithelial migration in response to an experimental model of Pseudomonas aeruginosa infection.

CONCLUSIONS

AD-HIES STAT3 mutations confer numerous abnormalities to airway epithelial cells in cell differentiation and host innate immunity, emphasizing their involvement in the pathogenesis of lung complications in Job syndrome. Therefore, therapies must address the epithelial defects as well as the previously noted immune cell defects to alleviate chronic infections in patients with Job syndrome.

Emergence of azole resistant-Aspergillus fumigatus infections during STAT3-deficiency

Introduction. Signal transducer and activator of transcription 3 (STAT3) deficiency is a rare primary immunodeficiency associated with increased susceptibility to bacterial and fungal infections, notably pulmonary aspergillosis.Aim. We describe the emergence of azole-resistant Aspergillus fumigatus infections in STAT3-deficient patients.Methodology. During a retrospective study of 13 pulmonary aspergillosis cases in STAT3-deficient patients conducted in France, we identified patients infected with azole-resistant A. fumigatus isolates.Results. Two out of the 13 STAT3-deficient patients with aspergillosis had azole-resistant A. fumigatus infection, indicating an unexpectedly high prevalence of resistance. The first patient with STAT3 deficiency presented several flares of allergic bronchopulmonary aspergillosis-like episodes. He was chronically infected with two azole-resistant A. fumigatus isolates (TR₃₄/L98). Despite prolonged antifungal treatment, including caspofungin and amphotericin B, the patient was not able to clear the azole-resistant A. fumigatus. The second patient had chronic cavitary pulmonary aspergillosis (CCPA). The A. fumigatus isolate was initially azole susceptible but harboured three F46Y, M172V and E427K point mutations. Despite prolonged antifungal therapies, lesions worsened and the isolate became resistant to all azoles. Surgery and caspofungin treatments were then required to cure CCPA. Resistance was probably acquired from the environment (TR₃₄/L98) in the first case whereas resistance developed under antifungal treatments in the second case. These infections required long-term antifungal treatments and surgery.Conclusions. The emergence of azole-resistant A. fumigatus infections in STAT3-deficiency dramatically impacts both curative and prophylactic antifungal strategies. Physicians following patients with primary immune-deficiencies should be aware of this emerging problem as it complicates management of the patient.

Spectrum of Pulmonary Aspergillosis in Hyper-IgE Syndrome with Autosomal-Dominant STAT3 Deficiency

BACKGROUND

Autosomal-dominant signal transducer and activator of transcription 3 (STAT3) deficiency predisposes to recurrent bacterial pneumonia, complicated by bronchiectasis and cavitations. Aspergillosis is a major cause of morbidity in these patients. However, its diagnosis, classification, and treatment are challenging.

OBJECTIVE

We aimed to assess the prevalence and describe the clinical, mycological, and radiological presentation and related therapy and outcome of Aspergillus infections of the respiratory tract in the STAT3-deficient patients of the National French cohort.

METHODS

We performed a retrospective study of all pulmonary aspergillosis cases in STAT3-deficient patients (n = 74). Clinical and mycological data were collected up to October 2015 and imaging was centralized.

RESULTS

Twenty-one episodes of pulmonary aspergillosis in 13 (17.5%) STAT3-deficient patients were identified. The median age at first episode was 13 years (interquartile range, 10-26 years). Ninety percent of patients had previous bronchiectasis or cavitations. Infections were classified as follows: 5 single aspergilloma, 9 chronic cavity pulmonary aspergillosis, 5 allergic bronchopulmonary aspergillosis-like disease, and 2 mixed forms of concomitant allergic bronchopulmonary aspergillosis-like disease and chronic cavity pulmonary aspergillosis. No invasive aspergillosis cases were identified. Aspergillus species were isolated in 71% of episodes and anti-Aspergillus antibodies in 93%. Eleven episodes were breakthrough infections. Antifungal treatment was prolonged, with a median of 13 months, and 6 patients (7 episodes) required surgery, with a high rate of postsurgical complications. One patient died and 6 had a relapse.

CONCLUSIONS

Chronic and allergic forms of aspergillosis occurred in 17.5% of STAT3-deficient patients, mostly in lung cavities. Almost half had recurrences, despite prolonged antifungal treatment and/or surgery.

Intensive care unit admission in patients with T cell lymphomas: clinical features and outcome

T cell non-Hodgkin lymphomas (T-NHLs) are aggressive malignancies which have a high risk of life-threatening complications. However, their prognosis in the intensive care unit (ICU) setting has not yet been assessed. We conducted a study including 87 ICU patients either with newly diagnosed T-NHLs or those undergoing first-line therapy admitted between January 1, 2000, and December 31, 2014. The primary subtypes were peripheral T cell lymphoma (PTCL) (n = 41, 47%), anaplastic large-cell lymphoma (ALCL) (n = 13, 15%), and adult T-leukaemia/lymphoma (ATLL) (n = 11, 13%). Six in every ten patients had malignancy-related complications (haemophagocytic syndrome 37%, tumour lysis syndrome 18% and hypercalcaemia 9%), while infections accounted for one quarter of ICU admissions. Nine fungal infections were documented, including six invasive aspergillosis. Urgent chemotherapy was started in the ICU in 59% of the patients, and urgent surgery was required in 13%. ICU and day-90 mortality were 22% and 41%, respectively. Multivariate analysis showed that SOFA score at day 1, age, sepsis and haemophagocytic syndrome were independent predictors of day-90 mortality. Compared to 66 ICU-matched controls with non-Hodgkin B cell lymphomas, patients with T-NHLs had a similar ICU survival. Overall survival rates of patients with T cell NHLs and B cell NHLs were 20% and 46%, respectively (hazard ratio for death associated with T cell NHLs 2.00 [1.12-3.58]). Patients with T cell NHLs had a very poor long-term outcome. Although the high rate of short-term survival suggests that an ICU trial is a reasonable option for patients newly diagnosed for the malignancy, extended stay in the ICU or further readmission should be considered only for highly selected patients who respond to the haematological treatment.