Macrophage Activation Syndrome as a Complication of Chronic Granulomatous Disease: A Case Report

Chronic granulomatous disease (CGD) presents with granuloma formation and lethal infections. It is inherited in an autosomal or X-linked recessive pattern. We describe a 10-month-old patient with a fatal secondary HLH as a CGD primary manifestation. We carried out an autopsy and found noncaseating granulomas, an aspergilloma in the lung, and hemophagocytosis. We performed a DHR assay on the patient's mother and grandmother, showing a bimodal pattern conclusive of X-linked CGD. Thus, our definitive diagnosis was CGD complicated by macrophage activation syndrome. CGD is caused by phagocytes' inability to control pathogens, resulting in granulomas. Secondary HLH is a severe complication and could be characterized by the proliferation of macrophages and T lymphocytes and the production of proinflammatory cytokines. The early suspicion of this presentation helps establish a specific treatment, and the study of the carriers helps determine the etiology.

Human OTULIN haploinsufficiency impairs cell-intrinsic immunity to staphylococcal α-toxin

The molecular basis of interindividual clinical variability upon infection with Staphylococcus aureus is unclear. We describe patients with haploinsufficiency for the linear deubiquitinase OTULIN, encoded by a gene on chromosome 5p. Patients suffer from episodes of life-threatening necrosis, typically triggered by S. aureus infection. The disorder is phenocopied in patients with the 5p- (Cri-du-Chat) chromosomal deletion syndrome. OTULIN haploinsufficiency causes an accumulation of linear ubiquitin in dermal fibroblasts, but tumor necrosis factor receptor-mediated nuclear factor κB signaling remains intact. Blood leukocyte subsets are unaffected. The OTULIN-dependent accumulation of caveolin-1 in dermal fibroblasts, but not leukocytes, facilitates the cytotoxic damage inflicted by the staphylococcal virulence factor α-toxin. Naturally elicited antibodies against α-toxin contribute to incomplete clinical penetrance. Human OTULIN haploinsufficiency underlies life-threatening staphylococcal disease by disrupting cell-intrinsic immunity to α-toxin in nonleukocytic cells.

COVID-19 in the Context of Inborn Errors of Immunity: a Case Series of 31 Patients from Mexico

INTRODUCTION

Patients with inborn errors of immunity (IEI) have a compromised or inappropriate immune response. Although they might be considered a high-risk group for severe SARS-CoV-2 infection, the reported impact of COVID-19 in these patients has been reassuring, while the differential susceptibility of distinct types of IEI remains unclear.

OBJECTIVE

We aimed to describe the findings and outcomes of our known patients with IEI who were diagnosed with COVID-19.

METHODS

In a retrospective study from March 2020 to February 2021, four centers in Mexico collected clinical, laboratory, and genetic data from pediatric and adult patients with known diagnoses of IEI who presented with COVID-19, based on compatible symptoms and positive SARS-CoV-2 testing or known household exposure.

RESULTS

We report 31 patients with known IEI from Mexico who presented with SARS-CoV-2 infection. Seventy-four percent were male, 52% were pediatric, and 81% survived. Their ages ranged from 5 months to 56 years, with a median of 17 years. Sixty-five percent had predominant antibody deficiencies, 48% were hospitalized, and 26% required ICU. Pediatric patients had a higher hospital admission rate than adults. Inpatient mortality was 40%, and ICU mortality rate was 63%. Forty-eight percent developed pneumonia, while 36% had evidence of hyperinflammation (4 adults and 7 children). Predominant laboratory features were lymphopenia and thrombocytopenia, seen in 70 and 44% of patients, respectively. The serum D-dimer median value was 2.6 (0.5-20.6) μg/mL, and the median highest ferritin value was 1015 (32-10,303) ng/mL. Intravenous immunoglobulin was used in 80% of patients. Other treatments included macrolides (39%) and corticosteroids (29%). Six patients died from secondary infection or uncontrolled systemic inflammation.

DISCUSSION

Although impaired immunity due to IEI may be a predisposing factor for severe COVID-19, most of our patients with IEI who acquired the SARS-CoV-2 infection developed a well-tolerated infection and survived, as have more than 80% of worldwide reported patients to date. An impaired immune or inflammatory response may be a predisposing factor for some and a protective factor for others. A systematic review of the literature could help identify those patients at risk of severe disease and complications. Healthcare-associated infections should be aggressively prevented.

Registro de Errores Innatos de la Inmunidad en un Hospital Pediátrico en México

RESUMEN Antecedentes. En México las inmunodeficiencias primarias o errores innatos de la inmunidad (EII) se han reportado desde el primer informe de la Sociedad Latinoamericana de Inmunodeficiencias Primarias (LASID, Latin American Society for immnunodeficiencies). En los últimos años se ha observado como diferentes hospitales de diferentes regiones de México se han afiliado al registro de las EII en la plataforma LASID, lo cual refleja objetivamente un mayor número de pacientes diagnosticados con EII.Resultados. El Hospital Pediátrico de Sinaloa (HPS) inició su afiliación al registro de pacientes con EII en la plataforma de LASID hace tres años, durante este periodo se inició el abordaje, diagnóstico y tratamiento de casos con EII. En este periodo se han diagnosticado y tratado doce casos con EII en el HPS. El rango de edad al momento del diagnóstico fue de 2 días a 16 años, el rango de inicio de los síntomas de 19 días a 4 años, con predominio del género masculino con 67%. La EII más frecuente fue la deficiencia predominantemente de anticuerpos (33.3%), seguida de defectos en fagocitos en número o función (16.6%), desordenes autoinflamatorios (16.6%), inmunodeficiencias que afectan la inmunidad celular y humoral (16.6%), inmunodeficiencias combinadas asociadas a hallazgos sindromáticos (8.3%) y defectos en la inmunidad intrínseca e innata (8.3%). El 84% de los pacientes recibió inmunoglobulina intravenosa. Se identificó la variante patogénica en el gen WAS en un caso con síndrome de Wiskott-Aldrich. Un paciente recibió trasplante de células progenitoras hematopoyética El 33.3% de los pacientes fallecieron, 25% por sepsis y el 8.3% por hemorragia masiva.Conclusiones. El registro de las EII en los centros hospitalarios de una nación permite conocer datos epidemiológicos, incidencia, prevalencia, diagnóstico y tratamiento que favorecerán al desarrollo de nuevas políticas sanitarias para la obtención de recursos y herramientas para mejorar los modelos de atención y tratamiento de los EII. Resaltamos la importancia de que cada centro hospitalario de México registre EII en el registro en línea de LASID.

Detection of a point mutation in IL12/23 receptor beta 1 chain in a Mexican patient with uncommon clinical feature. (58.5)

Mendelian susceptibility to mycobacterial disease (MSMD) is a heterogenous syndrome. The clinical characteristics include repetitive local infection and in some cases dissemination. In this work we analyzed a 5 years old boy with an uncharacterized mycobacterial infection. His parents are first degree cousins. Blood samples were collected and cultured 48 hours with medium, BCG or BCG+IL-12. Supernatants were assayed for IFN-γ by ELISA. PBMC were cultured with PMA-Ionomicyn and IL12R was measured by flow cytometry. We found low production of IFN γ after stimulation with BCG+IL12 that seems to correlate with an IL-12R defect. Flow cytometry showed a decrease of IL-12RB1 expression. Sequencing revealed a point mutation (A182T), which generates E61G change in the extracellular domain. Furthermore, the uncommon clinical features in this case might suggest another primary immunodeficiency.

Germline CYBB mutations that selectively affect macrophages in kindreds with X-linked predisposition to tuberculous mycobacterial disease

Germline mutations in CYBB, the human gene encoding the gp91(phox) subunit of the phagocyte NADPH oxidase, impair the respiratory burst of all types of phagocytes and result in X-linked chronic granulomatous disease (CGD). We report here two kindreds in which otherwise healthy male adults developed X-linked recessive Mendelian susceptibility to mycobacterial disease (MSMD) syndromes. These patients had previously unknown mutations in CYBB that resulted in an impaired respiratory burst in monocyte-derived macrophages but not in monocytes or granulocytes. The macrophage-specific functional consequences of the germline mutation resulted from cell-specific impairment in the assembly of the NADPH oxidase. This 'experiment of nature' indicates that CYBB is associated with MSMD and demonstrates that the respiratory burst in human macrophages is a crucial mechanism for protective immunity to tuberculous mycobacteria.

[Severe congenital neutropenia]

Severe congenital neutropenia is a primary immunodeficiency; the lack of maturation of neutrophil precursor in bone marrow and severe neutropenia are the subjacent characteristics which explain a marked susceptibility to severe and recurrent infections; bacteria and fungi are the most common etiologic agents. We report the case of an infant with severe congenital neutropenia that began at 4 days from birth with perianal abscess infections, sepsis, liver abscess, gingivitis and oral ulcers; she required multiple hospitalizations because of the severity of the infections. Isolated agents were Pseudomonas aeruginosa, Staphylococcus hominis and Klebsiella sp. The bone marrow examination showed maturation arrest of myeloid forms, thus confirming the diagnosis of severe congenital neutropenia. Granulocyte colony-stimulating factor was started. The severe congenital neutropenia should be considered in patients with neutropenia and infections in the first month of life. Early diagnosis and treatment improve survival and quality of life of these patients.

[An overview of primary immunodeficiency in Mexico]

Primary immunodeficiencies are rare immunologic diseases whose main characteristics are recurrent infections. These diseases are frequently unsuspected and the delayed diagnosis makes complications irreversible with the consequent poor quality of life. In Mexico, primary immunodeficiencies have a low prevalence, which is secondary to under-diagnosis and the lack of specialized laboratory studies in most hospitals. Since there is a registration of primary immunodeficiency cases in Europe and other developed countries, it is possible to estimate the incidence of primary immunodeficiencies and to elaborate guidelines of diagnosis and treatment. In our country we do not have any epidemiological registry; however, from 1998 to 2004 the number of cases of primary immunodeficiency has increased; the minimal incidence calculated is 0.16 to 0.24 per 100,000 births for chronic granulomatous disease, severe combined immunodeficiency and X linked agammaglobulinemia, this data is still very low compared to other international registries. We present an epidemiological review of primary immunodeficiency prevalence in Mexico compared to some international reports.

[Satisfactory evolution of a patient diagnosed in childhood with Bruton's disease]

Bruton's agammaglobulinemia is a primary immunodeficiency with a disease onset during the first months of age, when the maternal serum immunoglobulin levels decrease. It is characterized by recurrent infections and agammaglobulinemia. We report the case of a 6-year-old male patient with third-degree consanguinity, product of a third pregnancy and complete immunization scheme. He had a history of oral candidiasis at the age of 3 months, chicken pox at the age of 7 months, and two episodes of complicated bronchopneumonia at the age of 1 year and 6 years. He was admitted to the hospital because of fever and cough. Examination of the chest showed rales and right basilar hypoventilation, and a blood cell count revealed leukocytosis and neutrophilia. The diagnosis of pneumonia was made. He was treated with IV antibiotics. Serum immunoglobulins were reported to be low (IgM 55 mg/dL, IgA 0.9 mg/dL, and IgG 199 mg/dL). With these findings the clinical diagnosis of X-linked agammaglobulinemia (ALX) was concluded. A molecular test was performed fining a BTK gene confirming the diagnosis of Bruton's disease. Therapy with intravenous IgG was started every 21 days. During his evolution, he presented three episodes of rhinosinusitis, one of suppurative otitis media, and four events of pneumonia that required 37 days of hospitalization. After hospital discharge, the patient was free of infections and he returned to his daily activities. In cases of recurrent and severe respiratory infections in children, we must consider primary immunodeficiency disease in the differential diagnosis, mainly antibiotic deficiency. Early diagnosis and treatment improves the survival and quality of life in these patients.

[Wiskott-Aldrich syndrome]

The Wiskott-Aldrich syndrome is a primary immunodeficiency characterized by congenital microthrombocytopenia, eczema and recurrent infections. This paper reports the case of a 3-year-6-month male patient, whose maternal uncle died at the age of 3 months due to fulminant sepsis from a pulmonary infection. The patient was a product of the first pregnancy, he was born at 27 weeks' gestation and weighed 1,400 g. As a neonate he was hospitalized during the first 2 months of life because of a low gastrointestinal bleeding, thrombocytopenia and severe infections. In the next 4 months and before coming to our hospital the infant was hospitalized 54 times. On admission he presented disseminated dermatosis, enlarged neck lymph nodes and psychomotor retardation. Laboratory studies revealed hemoglobin 8.1 g/dL, platelets 31,000/uL, mean platelet volume 5.6 fL, IgM 39.3 mg/dL, IgA 67 mg/dL, IgG 1,380 mg/dL. On several occasions he received globular packages and platelet concentrates. The infusion of immunoglobulin G was started every 21 days. Bone marrow transplantation was delayed due to the complications that merited 13 hospitalizations and severe thrombocytopenia, low gastrointestinal bleeding, septic arthritis, infectious gastroenteritis, chronic suppurative otitis media and severe folliculitis. At the age of 4 years BMT of cord was performed, and 26 days after transplantation he presented septic shock and died. The prognosis of bone marrow transplantation in Wiskott-Aldrich syndrome and in other primary immunodeficiencies depends on the promptness of its performance at early stages in life. It is important that the first contact physicians be aware of the primary immunodeficiency signs and symptoms.

[A report of a family with chronic granulomatous disease with a gp91phox disorder]

The chronic granulomatous disease is a primary immunodeficiency with a defect of the phagocytosis process; its main alteration resides in the incapacity of the NADPH oxidase system to produce reactive oxygen species capable of destruct pathogenic organisms such as bacteria, fungus and mycobacteria. Patients are susceptible to severe and mild infections, mainly pneumonias, linfadenitis and gastroenteritis that tend to be repetitive; in addition, they presented granulomatous inflammation and autoimmunity. We presented the case of two brothers with X-linked chronic granulomatous disease with alteration in the sub-unit gp91Phox; heredofamilial background was endogamy and consanguinity. Both patients suffered severe infections, frequent abscesses and a poor growth. Diagnosis was confirmed with nitroblue tetrazolium test. During their evolution, the patients presented also BCGitis, BCGosis and septic shock. They began prophylactic treatment with trimetoprim sulfametoxazole and itraconazole, as well as gamma interferon, with favorable response, presenting a lower amount of infectious episodes, as well as a recovery of their weight and height. The early diagnosis of the patients has improved their prognosis.