Background Inherited macrothrombocytopenia comprises a heterogeneous group of platelet disorders characterized by low platelet counts and abnormally enlarged platelets, with clinical presentations ranging from absent to mild bleeding tendencies. Multiple genes involved in platelet cytoskeletal architecture and thrombopoiesis have been identified; among them, TUBA8 was recently recognized to encode tubulin alpha‐8, a critical component contributing to microtubule polymerization and organization. Case presentation The patient was a 12‐year‐old boy being treated for thrombocytopenia who presented with eczematous lesions and atopic symptoms. The patient had significantly elevated immunoglobulin E (IgE) of 9300 IU/mL. In whole exome sequencing; the patient revealed an autosomal dominant mutation in TUBA8 gene, a variant of unknown significance, which is known to cause macrothrombocytopenia. Conclusion This report of the unusual coexistence of macrothrombocytopenia, markedly elevated serum IgE, and a heterozygous TUBA8 variant of uncertain significance (VUS) underscore the importance of evaluating extra‐hematologic features in tubulin‐associated disorders and warrant further functional studies to delineate the role of α8‐tubulin in immune homeostasis.
Adult-onset Still’s disease (AOSD) is a diagnosis of exclusion and may be difficult to recognize when infection and drug hypersensitivity coexist. A 31-year-old woman presented with high-spiking fever, arthralgia, and a generalized eruption after ampicillin exposure. Initial investigations for infection and autoimmune disease were unrevealing. Her clinical course was subsequently complicated by severe nosocomial infection and recurrent eruptions during antibiotic treatment. Recurrent high-spiking fever and a fever-associated eruption after apparent clinical improvement of infection supported AOSD as the working diagnosis. However, uncertainty regarding the rash and overlapping infectious and drug-related features limited confident retrospective confirmation of the Yamaguchi classification criteria. Following infection control, intravenous methylprednisolone pulse therapy followed by cyclosporine resulted in rapid clinical improvement. This case illustrates the diagnostic complexity of AOSD in the setting of nosocomial infection and antibiotic hypersensitivity.
Chylothorax and pseudochylothorax are both rare forms of pleural effusion characterized by a milky appearance of the pleural fluid. Despite their similarities, they have distinct etiologies, clinical implications, and medical management strategies. Pleural fluid analysis of cholesterol and triglyceride levels is crucial to differentiate between them, establish a proper diagnosis, and guide clinical evaluation and treatment. This case report describes an uncommon presentation of pseudochylothorax associated with long-standing rheumatoid arthritis (RA) in a patient with no prior history of pleural disease.
Corn‐dependent exercise‐induced anaphylaxis (food‐dependent exercise‐induced anaphylaxis [FDEIA]) is rare, and its causative allergens remain poorly defined. Here, we report a case of corn‐dependent FDEIA and investigate candidate IgE‐binding proteins using immunological and proteomic analyses. A 13‐year‐old boy with a history of buckwheat allergy developed recurrent anaphylaxis during exercise after ingesting corn‐containing foods. An exercise challenge after ingesting 272 g of sweet corn reproduced the symptoms and confirmed the diagnosis. Corn‐specific IgE was 3.72 UA/mL, and skin prick testing was positive. IgE immunoblotting revealed patient‐specific bands at ~45 and 60 kDa. Two‐dimensional immunoblotting and mass spectrometry identified globulin‐1S (GLB1) and other proteins as candidate IgE‐binding proteins in this patient. Sequence analysis revealed significant local sequence similarity between maize GLB1 and buckwheat Fag e 5 within the second cupin domain. These findings identify GLB1 as a candidate IgE‐binding protein in this patient with corn‐dependent FDEIA. Although sequence similarities were observed between maize GLB1 and buckwheat Fag e 5, their immunological and clinical significance remains unclear, and further studies are required to determine whether cross‐reactivity exists.
Background X‐linked agammaglobulinemia (XLA) is an inherited primary immunodeficiency characterized by impaired B‐cell maturation, profound hypogammaglobulinemia, and susceptibility to recurrent bacterial infections. Lifelong immunoglobulin replacement therapy (IGRT) is essential to reduce infectious complications, but treatment interruptions may markedly increase infection risk. Case Presentation An 18‐year‐old male with XLA discontinued regular intravenous immunoglobulin (IVIG) replacement for 12 months because of financial constraints. He presented with fever, productive cough, pleuritic chest pain, hypoxemia, leukocytosis, and elevated inflammatory markers. His serum IgG level was 98.10 mg/dL. Chest computed tomography showed consolidation of the right middle and lower lobes without cavitation or bronchiectasis. Blood cultures and molecular testing of respiratory specimens identified both Klebsiella pneumoniae and Streptococcus pneumoniae , supporting polymicrobial pneumonia with bloodstream infection. A pathogenic Bruton tyrosine kinase ( BTK ) c.1522G >A (p.Ala508Thr) variant was confirmed. Intravenous imipenem–cilastatin and levofloxacin were administered according to antimicrobial susceptibility results. After 5 days, fever and oxygen dependence persisted despite improvement in leukocytosis. Following consultation with the hematology department, IVIG was readministered at 400 mg/kg, followed within 48 h by defervescence, discontinuation of supplemental oxygen, and marked improvement in inflammatory markers. He was discharged on hospital day 14, resumed IVIG every 4 weeks, and had no significant residual pulmonary lesion on follow‐up computed tomography 1 month later. Conclusion This case highlights the consequences of interrupted immunoglobulin replacement in XLA and the importance of combining pathogen‐directed antimicrobial therapy with restoration of humoral protection in severe infection. It also illustrates how financial barriers may compromise continuity of lifelong treatment.
