An infant with repeated respiratory infections and failure to thrive

Clinical, Immunological, and Molecular Features of Severe Combined Immune Deficiency: A Multi-Institutional Experience From India

Background

Severe Combined Immune Deficiency (SCID) is an inherited defect in lymphocyte development and function that results in life-threatening opportunistic infections in early infancy. Data on SCID from developing countries are scarce.

Objective

To describe clinical and laboratory features of SCID diagnosed at immunology centers across India.

Methods

A detailed case proforma in an Excel format was prepared by one of the authors (PV) and was sent to centers in India that care for patients with primary immunodeficiency diseases. We collated clinical, laboratory, and molecular details of patients with clinical profile suggestive of SCID and their outcomes. Twelve (12) centers provided necessary details which were then compiled and analyzed. Diagnosis of SCID/combined immune deficiency (CID) was based on 2018 European Society for Immunodeficiencies working definition for SCID.

Results

We obtained data on 277 children; 254 were categorized as SCID and 23 as CID. Male-female ratio was 196:81. Median (inter-quartile range) age of onset of clinical symptoms and diagnosis was 2.5 months (1, 5) and 5 months (3.5, 8), respectively. Molecular diagnosis was obtained in 162 patients - IL2RG (36), RAG1 (26), ADA (19), RAG2 (17), JAK3 (15), DCLRE1C (13), IL7RA (9), PNP (3), RFXAP (3), CIITA (2), RFXANK (2), NHEJ1 (2), CD3E (2), CD3D (2), RFX5 (2), ZAP70 (2), STK4 (1), CORO1A (1), STIM1 (1), PRKDC (1), AK2 (1), DOCK2 (1), and SP100 (1). Only 23 children (8.3%) received hematopoietic stem cell transplantation (HSCT). Of these, 11 are doing well post-HSCT. Mortality was recorded in 210 children (75.8%).

Conclusion

We document an exponential rise in number of cases diagnosed to have SCID over the last 10 years, probably as a result of increasing awareness and improvement in diagnostic facilities at various centers in India. We suspect that these numbers are just the tip of the iceberg. Majority of patients with SCID in India are probably not being recognized and diagnosed at present. Newborn screening for SCID is the need of the hour. Easy access to pediatric HSCT services would ensure that these patients are offered HSCT at an early age.

The piglet mycobiome during the weaning transition: a pilot study1

The importance of the microbiota in the gastrointestinal tract of animals is recognized as a critical player in host health. Recently, the significance of the mycobiome has been recognized, but culture-independent studies are limited, especially in swine. Weaning is a time of stress, dietary changes, and a predisposition to infections, making it a time point of interest to industry. In this pilot study, we sought to assess and characterize the mycobiome in the feces of swine from birth through the critical weaning transition to investigate the mycobiome population and its temporal dynamics in piglet feces. Cultured fecal samples demonstrate a significant increase in fungal burden following weaning that does not differ from adult levels, suggesting stable colonization. Culturable fungi were not found in any environmental samples tested, including water, food, sow milk or colostrum. To determine the fungal diversity present and to address the problem of unculturable fungi, we performed a pilot study utilizing ITS and 16S rRNA focused primers for high-throughput sequencing of fungal and bacterial species, respectively. Bacterial populations increase in diversity over the experimental timeline (days 1 to 35 postbirth), but the fungal populations do not demonstrate the same temporal trend. Following weaning, there is a dynamic shift in the feces to a Saccharomycetaceae-dominated population. The shift in fungal population was because of the dominance of Kazachstania slooffiae, a poorly characterized colonizer of animal gastrointestinal tracts. This study provides insights into the early colonization and subsequent establishment of fungi during the weaning transition in piglets. Future studies will investigate the effect of the mycobiome on piglet growth and health during the weaning transition.

Infectious and non-infectious complications in primary immunodeficiency disorders: an autopsy study from North India

BACKGROUND

Primary immunodeficiency disorders (PID) include a wide spectrum of inherited disorders characterised by functional abnormalities of one or more components of the immune system. Recent updates from the genomic data have contributed significantly to its better understanding with identification of new entities. Diagnosis is always challenging due to their variable clinical presentation. With the evolution of molecular diagnosis, many of these children are being diagnosed early and offered appropriate therapy. However, in developing countries, early diagnosis is still not being made: as a result these patients succumb to their disease. Autopsy data on PID is notably lacking in the literature with histopathological evaluation of PID being limited to rare case reports.

OBJECTIVE

To analyse the clinical, immunologic (including mutational) and morphologic features at autopsy in 10 proven and suspected cases of primary immunodeficiency disorders diagnosed at our Institute over the past decade.

METHODS

Study includes a detailed clinico-pathological analysis of 10 proven and suspected cases of primary immunodeficiency disorders.

RESULTS

A varied spectrum of infectious and non-infectious complications were identified in these cases of which fungal infections were found to be more frequent compared with viral or bacterial infections. Rare and novel morphological findings, like granulomatous involvement of the heart in a patient with chronic granulomatous disease, systemic amyloidosis in a teenage girl with X-linked agammaglobulinemia, are highlighted which is distinctly lacking in the literature.

CONCLUSIONS

The present study is perhaps the first autopsy series on PID. Even in the molecular era, such analysis is still important, as correlation of pathological features with clinical symptoms provides clues for a timely diagnosis and appropriate therapeutic intervention.