Pneumocystis jiroveci pneumonia and GATA2 deficiency: Expanding the spectrum of the disease

The different faces of GATA2 deficiency: implications for therapy and surveillance

GATA2 deficiency is one of the most common genetic predispositions to pediatric myelodysplastic syndrome (MDS) in children and adolescents. The wide spectrum of disease comprises, among others, hematological, immunological and pulmonary manifestations, as well as occasionally distinct organ anomalies. Due to the elevated risk of progression, nearly all individuals with GATA2-related MDS eventually undergo a hematopoietic stem cell transplantation (HSCT) at some point in their lives. Nevertheless, the optimal timing, method, and even the indication for HSCT in certain cases are still matter of debate and warrant further research. In this article, we report five patients with different hematological and immunological manifestations of GATA2 deficiency ranging from immunodeficiency and refractory cytopenia of childhood without chromosomal aberrations to relapsed MDS-related acute myeloid leukemia. We discuss the adopted strategies, including intensity of surveillance, indication and timing of HSCT, based on morphological, clinical and molecular markers, as well as individual patient needs. We conclude that a better characterization of the natural disease course, a better understanding of the prognostic significance of somatic aberrations and a thorough evaluation of patients´ perspectives and preferences are required to achieve a personalized approach aimed at improving the care of these patients.

Invasive mucorales sinusitis in a young patient with Emberger syndrome and newly diagnosed AML: A case report and literature review of invasive fungal infections in GATA2 deficiency

Germline pathogenic variants (PVs) in the gene encoding the GATA2 transcription factor can result in profound reductions of monocytes, dendritic cells, natural killer cells and B cells. GATA2 PVs are associated with an increased risk of myeloid malignancies and a predisposition to nontuberculous mycobacterial and human papillomavirus infections. Additionally, invasive fungal infections (IFIs) have been reported in individuals with GATA2 PVs, even in the absence of myeloid malignancies. In this report, we present the case of a 40-year-old man with Emberger syndrome (GATA2 mutation, recently diagnosed acute myeloid leukaemia [AML] and history of lymphedema with hearing loss) who developed Mucorales sinusitis while receiving his first course of remission induction chemotherapy. Additionally, we review the literature on all published cases of proven IFIs in patients with GATA2 PVs. Clinicians should be aware that patients with GATA2 PVs could be vulnerable to opportunistic IFIs, even in the absence of AML and antineoplastic therapy. Furthermore, the distinctly unusual occurrence of mucormycosis during the first course of induction chemotherapy for AML in our patient indicates that patients with germline GATA2 PVs receiving induction chemotherapy for AML might be at high risk for early onset of IFIs due to aggressive, opportunistic moulds.

Trends in the Epidemiology of Pneumocystis Pneumonia in Immunocompromised Patients without HIV Infection

The increasing morbidity and mortality of life-threatening Pneumocystis pneumonia (PCP) in immunocompromised people poses a global concern, prompting the World Health Organization to list it as one of the 19 priority invasive fungal diseases, calling for increased research and public health action. In response to this initiative, we provide this review on the epidemiology of PCP in non-HIV patients with various immunodeficient conditions, including the use of immunosuppressive agents, cancer therapies, solid organ and stem cell transplantation, autoimmune and inflammatory diseases, inherited or primary immunodeficiencies, and COVID-19. Special attention is given to the molecular epidemiology of PCP outbreaks in solid organ transplant recipients; the risk of PCP associated with the increasing use of immunodepleting monoclonal antibodies and a wide range of genetic defects causing primary immunodeficiency; the trend of concurrent infection of PCP in COVID-19; the prevalence of colonization; and the rising evidence supporting de novo infection rather than reactivation of latent infection in the pathogenesis of PCP. Additionally, we provide a concise discussion of the varying effects of different immunodeficient conditions on distinct components of the immune system. The objective of this review is to increase awareness and knowledge of PCP in non-HIV patients, thereby improving the early identification and treatment of patients susceptible to PCP.

GATA2 Deficiency: Predisposition to Myeloid Malignancy and Hematopoietic Cell Transplantation

PURPOSE OF REVIEW

GATA2 deficiency is a haploinsufficiency syndrome associated with a wide spectrum of disease, including severe monocytopenia and B and NK lymphopenia, predisposition to myeloid malignancies, human papillomavirus infections, and infections with opportunistic organisms, particularly nontuberculous mycobacteria, herpes virus, and certain fungi. GATA2 mutations have variable penetrance and expressivity with imperfect genotype-phenotype correlations. However, approximately 75% of patients will develop a myeloid neoplasm at some point. Allogeneic hematopoietic cell transplantation (HCT) is the only currently available curative therapy. Here, we review the clinical manifestations of GATA2 deficiency, characterization of the hematologic abnormalities and progression to myeloid malignancy, and current HCT practices and outcomes.

RECENT FINDINGS

Cytogenetic abnormalities are common with high rates of trisomy 8, monosomy 7, and unbalanced translocation der(1;7) and may suggest an underlying GATA2 deficiency in patients presenting with myelodysplastic syndrome (MDS). Mutations in ASXL1 and STAG2 are the most frequently encountered somatic mutations and are associated with lower survival probability. A recent report of 59 patients with GATA2 deficiency who underwent allogenic HCT with myeloablative, busulfan-based conditioning and post-transplant cyclophosphamide reported excellent overall and event-free survival of 85% and 82% with reversal of disease phenotype and low rates of graft versus host disease. Allogeneic HCT with myeloablative conditioning results in disease correction and should be considered for patients with a history of recurrent, disfiguring and/or severe infections, organ dysfunction, MDS with cytogenetic abnormalities, high-risk somatic mutations or transfusion dependence, or myeloid progression. Improved genotype/phenotype correlations are needed to allow for greater predictive capabilities.

Of Mycelium and Men: Inherent Human Susceptibility to Fungal Diseases

In medical mycology, the main context of disease is iatrogenic-based disease. However, historically, and occasionally, even today, fungal diseases affect humans with no obvious risk factors, sometimes in a spectacular fashion. The field of “inborn errors of immunity” (IEI) has deduced at least some of these previously enigmatic cases; accordingly, the discovery of single-gene disorders with penetrant clinical effects and their immunologic dissection have provided a framework with which to understand some of the key pathways mediating human susceptibility to mycoses. By extension, they have also enabled the identification of naturally occurring auto-antibodies to cytokines that phenocopy such susceptibility. This review provides a comprehensive update of IEI and autoantibodies that inherently predispose humans to various fungal diseases.

Bacille Calmette-Guerin Complications in Newly Described Primary Immunodeficiency Diseases: 2010-2017

Bacille Calmette–Guerin (BCG) vaccine is widely used as a prevention strategy against tuberculosis. BCG is a live vaccine, usually given early in life in most countries. While safe to most recipients, it poses a risk to immunocompromised patients. Several primary immunodeficiency diseases (PIDD) have been classically associated with complications related to BCG vaccine. However, a number of new inborn errors of immunity have been described lately in which little is known about adverse reactions following BCG vaccination. The aim of this review is to summarize the existing data on BCG-related complications in patients diagnosed with PIDD described since 2010. When BCG vaccination status or complications were not specifically addressed in those manuscripts, we directly contacted the corresponding authors for further clarification. We also analyzed data on other mycobacterial infections in these patients. Based on our analysis, around 8% of patients with gain-of-function mutations in STAT1 had mycobacterial infections, including localized complications in 3 and disseminated disease in 4 out of 19 BCG-vaccinated patients. Localized BCG reactions were also frequent in activated PI3Kδ syndrome type 1 (3/10) and type 2 (2/18) vaccinated children. Also, of note, no BCG-related complications have been described in either CTLA4 or LRBA protein-deficient patients; and not enough information on BCG-vaccinated NFKB1 or NFKB2-deficient patients was available to drive any conclusions about these diseases. Despite the high prevalence of environmental mycobacterial infections in GATA2-deficient patients, only one case of BCG reaction has been reported in a patient who developed disseminated disease. In conclusion, BCG complications could be expected in some particular, recently described PIDD and it remains a preventable risk factor for pediatric PIDD patients.

Germline GATA2 Mutation and Bone Marrow Failure

GATA2 deficiency is an immunodeficiency and bone marrow failure disorder caused by pathogenic variants in GATA2. It is inherited in an autosomal-dominant pattern or can be due to de novo sporadic germline mutation. Patients commonly have B-cell, dendritic cell, natural killer cell, and monocytopenias, and are predisposed to myelodysplastic syndrome, acute myeloid leukemia, and chronic myelomonocytic leukemia. Patients may suffer from disseminated human papilloma virus and mycobacterial infections, pulmonary alveolar proteinosis, and lymphedema. The bone marrow eventually takes on a characteristic hypocellular myelodysplasia with loss of monocytes and hematogones, megakaryocytes with separated nuclear lobes, micromegakaryocytes, and megakaryocytes with hypolobated nuclei.