Novel variant in <i>IGHM</i> gene in a patient with agammaglobulinemia: A case report of a preschool child presenting with recurrent pneumonia
Bibliographic record
Abstract
Introduction: Agammaglobulinemia is a primary immunodeficiency characterized by absent B cells and originates from X-linked or autosomal mutations affecting B cell maturation. While the most common agammaglobulinemia is X-linked, one well-documented site of autosomal recessive agammaglobulinemia is within the immunoglobulin μ heavy chain protein, encoded by the IGHM gene. Such variants frequently result in clinical presentations of recurrent bacterial infections early in life. Aim: To describe a case of a five-year-old female with agammaglobulinemia resulting from a novel homozygous IGHM variant, presenting with pneumonia complicated by empyema and H. influenzae bacteremia. Methods: Case data was compiled retrospectively from the patient’s medical chart, including relevant laboratory testing for immunoglobulins, quantitative B cell subsets, and genetic testing using a primary immunodeficiency panel. Results: The proband is a 5-year-old female with a history of recurrent pneumonia, presenting with H. influenzae bacteremia in the context of pneumonia complicated by an empyema. Investigations revealed low immunoglobulin levels, absent vaccine responses, and undetectable B cells on flow cytometry. Genetic testing revealed a novel homozygous variant in the IGHM gene: c.775T>C, p.Trp259Arg. Conclusion: Autosomal recessive agammaglobulinemia is a rare but severe, treatable disorder of the immune system which typically presents in early childhood. Hypomorphic mutations, while less commonly reported in the literature, are an important consideration in atypical presentations of primary immunodeficiencies, such as in the case presented. Statement of Novelty: Herein, we report a case of agammaglobulinemia presenting with a novel homozygous variant in the IGHM gene leading to later onset agammaglobulinemia in a 5-year-old female.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.002 |
| Meta-epidemiology (narrow) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.004 | 0.003 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".