X-Linked Lymphoproliferative Syndrome: A Spectrum of Clinical and Immunological Profile and Novel Pathogenic Variants from Chandigarh, India.

INTRODUCTION: X-linked lymphoproliferative syndrome (XLP) is a rare primary immune deficiency. Two types of XLP have been described: XLP-1 and XLP-2. METHODS: We found 7 patients with XLP (3 had XLP-1 and 4 had XLP-2) after reviewing the data from Pediatric Immunodeficiency Clinic from 1997 to 2021. RESULTS: Mean age at diagnosis was 3.8 years, and mean delay in diagnosis was 2.6 years. Five patients had recurrent episodes of infections. Four patients developed at least one episode of hemophagocytic lymphohistiocytosis (HLH) (2 with XLP-1 and 2 with XLP-2). Of these, 2 had recurrent HLH (both with XLP-2). Epstein-Barr virus (EBV) infection was detected in 2 (1 with XLP-1 and 1 with XLP-2). Both these patients had HLH. One child with XLP-2 had inflammatory bowel disease. Hypogammaglobulinemia was seen in 3 (2 with XLP-1 and 1 with XLP-2). Genetic analysis showed previously reported variants in 5, while 2 had novel variants (one in exon 7 of XIAP gene [c.1370dup p.Asn457Lysfs Ter16] and other had splice site variant in intron 1 of SH2D1A gene [c.138-2_138-1insG]). Episodes of HLH were managed with intravenous immunoglobulin (IVIg), methylprednisolone, oral prednisolone, cyclosporine, and rituximab. Inflammatory bowel disease was managed using oral prednisolone and azathioprine. One patient underwent haploidentical hematopoietic stem cell transplantation. One child with XLP-2 and WAS died because of fulminant pneumonia. DISCUSSION/CONCLUSIONS: XLP should be considered as a strong possibility in any patient with features of HLH, repeated infections with hypogammaglobulinemia, persistent EBV infection, and early-onset IBD.

Clinical, immunological and molecular profiles of DOCK8 deficiency in six patients from a tertiary care centre in North India.

BACKGROUND: Dedicator of cytokinesis protein 8 (DOCK8) deficiency is an autosomal recessive form of combined immunodeficiency. This rare disorder is characterized by an increased predisposition to allergy, autoimmunity and malignancies. OBJECTIVES: To analyse clinical, immunological and molecular profiles of patients with DOCK8 deficiency. METHODS: Clinic records of all patients attending the primary immunodeficiency clinic from 2018 to 2021 were reviewed. Six patients from five families were found to have DOCK8 deficiency. RESULTS: Median age at diagnosis was 7.5 years (range 2-13), with a male/female ratio of 5 : 1. Among the six patients, recurrent eczematous skin lesions were the predominant cutaneous manifestation, present in five patients (83%). Warts and molluscum contagiosum were evident in two patients (33%) and one patient (16%), respectively. Two patients had recalcitrant prurigo nodularis lesions and two had epidermodysplasia verruciformis-like lesions. Food allergies and asthma were reported by one patient each. Of the six patients, recurrent sinopulmonary infections were detected in five (83%). Epstein-Barr virus-driven non-Hodgkin lymphoma with liver metastases was the only case of malignancy, in a 4-year-old boy. IgE was elevated in all patients. Lymphopenia and eosinophilia were observed in three patients (50%) and five patients (83.3%), respectively. Genetic analysis showed DOCK8 pathogenic variants in all patients: homozygous deletion mutations in two patients, compound heterozygous deletion mutations in one, and homozygous nonsense mutations in two. A novel pathogenic homozygous missense variant in the DOCK8 gene was identified in one patient. CONCLUSIONS: DOCK8 deficiency should be considered as a possibility in any patient with early onset eczema, cutaneous viral infections and increased predisposition to allergy, autoimmunity and malignancy.

Delay in diagnosis is the most important proximate reason for mortality in hereditary angio-oedema: our experience at Chandigarh, India.

BACKGROUND: Hereditary angio-oedema (HAE) is a rare autosomal dominant disorder characterized clinically by recurrent episodes of nonpruritic subcutaneous and/or submucosal oedema. Laryngeal oedema is the commonest cause of mortality in patients with HAE. Prior to the availability of first-line treatment options for the management of HAE, mortality was as high as 30%. Mortality has significantly declined in countries where first-line treatment options are available and patients can access these therapies. There is a paucity of literature on the outcomes of patients with HAE in developing countries where availability of and access to first-line treatment options are still a challenge. OBJECTIVES: To report our experience on mortality in patients with HAE and to report factors associated with the death of these patients. METHODS: We carried out a record review of all patients diagnosed with HAE between January 1996 and August 2022. Families with HAE who had reported the death of at least one family member/relative from laryngeal oedema were studied in detail. RESULTS: Of the 65 families (170 patients) registered in the clinic, 16 families reported the death of at least one family member/relative from laryngeal oedema (total of 36 deaths). Of these 16 families, 14 reported that 1 or more family members had experienced at least 1 attack of laryngeal oedema. One patient died during follow-up when she was taking long-term prophylaxis with stanozolol and tranexamic acid, while the remaining 35 patients were not diagnosed with HAE at the time of their death. At the time of death of all 36 patients, at least 1 other family member had symptoms suggestive of HAE, but the diagnosis was not established for the family. CONCLUSIONS: To our knowledge, this is the largest single-centre cohort of patients with HAE in India reporting mortality data and factors associated with death in these families. The delay in diagnosis is the most important reason for mortality.

Meningoencephalitis in primary antibody deficiency: Our experience from northwest India.

BACKGROUND/OBJECTIVES: Patients with primary antibody deficiency (PAD) are predisposed to develop meningoencephalitis, often considered to be enteroviral. However, there is a paucity of literature on this subject, and there are no studies from developing countries. METHODS: We analyzed our cohort of children with PAD who developed meningoencephalitis. RESULTS: This complication was observed in 13/135 (10.4%) patients with PAD - 5 patients had X-linked agammaglobulinemia (XLA), 7 had common variable immunodeficiency (CVID) and 1 had suspected nuclear factor kappa B essential modulator (NEMO) defect. Mean age at onset of neurological illness was 9.3 years. Presenting features included seizures (n=8), neurodevelopmental delay (n=2), regression of milestones (n=2), and acute flaccid paralysis (n=1). Trough IgG levels were found to be low in 12/13 patients at the time of development of neurological symptoms. Herpes simplex virus (HSV), cytomegalovirus (CMV), and Streptococcus pneumoniae were isolated in 1 each. Eight (72.7%) patients had altered signal hyperintensities in gray matter and deep white matter on magnetic resonance imaging (MRI), while 4 patients showed global cerebral atrophy. All patients were treated with high-dose intravenous immunoglobulin (IVIg). Fluoxetine was given to 3 patients. Eight patients in the present series have died, 3 have recovered with varying degrees of neurological sequelae and 2 patients are showing gradual recovery. CONCLUSIONS: To conclude, meningoencephalitis is an uncommon complication in patients with PAD and is associated with high morbidity and mortality. Early diagnosis of immune deficiency and initiation of replacement immunoglobulin therapy may prevent the development of neurological complications.

Kawasaki disease malingering as juvenile dermatomyositis: case-based review : Myositis in Kawasaki disease.

Kawasaki disease (KD) is a medium vessel vasculitis that predominantly affects children below 5. Diagnosis of KD is based on the presence of characteristic clinical manifestations as there are no definite diagnostic laboratory investigations for the diagnosis of this disease. Presence of atypical clinical features such as myositis often pose diagnostic challenge for the treating physicians. Presence of myositis and severe muscular weakness in KD is distinctly unusual and may lead to delays in diagnosis and administration of definite therapy. We report a 10-year-old boy who presented with fever, rash and proximal muscle and pharyngeal weakness. A clinical possibility of toxic shock syndrome or juvenile dermatomyositis was initially considered. However, he continued to have fever and developed periungual peeling of skin in fingers. Hence, a possibility of KD with myositis was considered. He showed prompt response to intravenous immunoglobulin and methylprednisolone. We also provide a review of similarly reported cases of KD myositis. It is important for clinicians to be aware of this atypical clinical presentation to avoid delays in diagnosis and treatment of KD.

Clinical and Genetic Profile of X-Linked Agammaglobulinemia: A Multicenter Experience From India.

Background: There is paucity of literature on XLA from developing countries. Herein we report the clinical and molecular profile and outcome in a multicenter cohort of patients with XLA from India. Methods: Data on XLA from all regional centers supported by the Foundation for Primary Immunodeficiency Diseases (FPID), USA and other institutions providing care to patients with PIDs were collated. Diagnosis of XLA was based on European Society for Immunodeficiencies (ESID) criteria. Results: We received clinical details of 195 patients with a provisional diagnosis of XLA from 12 centers. At final analysis, 145 patients were included (137 'definite XLA' and eight 'probable/possible XLA'). Median age at onset of symptoms was 12.0 (6.0, 36.0) months and median age at diagnosis was 60.0 (31.5, 108) months. Pneumonia was the commonest clinical manifestation (82.6%) followed by otitis media (50%) and diarrhea (42%). Arthritis was seen in 26% patients while 23% patients developed meningitis. Bronchiectasis was seen in 10% and encephalitis (likely viral) in 4.8% patients. Pseudomonas aeruginosa was the commonest bacterial pathogen identified followed by Streptococcus pneumoniae, Staphylococcus aureus and Klebsiella pneumoniae. Molecular analysis revealed 86 variants in 105 unrelated cases. Missense variants in BTK gene were the most common (36%) followed by frameshift (22%) and nonsense variants (21%). Most pathogenic gene variants (53%) were clustered in the distal part of gene encompassing exons 14-19 encoding for the tyrosine kinase domain. Follow-up details were available for 108 patients. Of these, 12% had died till the time of this analysis. The 5-year and 10-year survival was 89.9% and 86.9% respectively. Median duration of follow-up was 61 months and total duration of follow-up was 6083.2 patient-months. All patients received intravenous immunoglobulin (IVIg) replacement therapy. However, in many patients IVIg could not be given at recommended doses or intervals due to difficulties in accessing this therapy because of financial reasons and lack of universal health insurance in India. Hematopoietic stem cell transplant was carried out in four (2.8%) patients. Conclusion: There was a significant delay in the diagnosis and facilities for molecular diagnosis were not available at many centers. Optimal immunoglobulin replacement is still a challenge.