Efficient detection of somatic UBA1 variants and clinical scoring system predicting patients with variants in VEXAS syndrome.

OBJECTIVES: To efficiently detect somatic UBA1 variants and establish a clinical scoring system predicting patients with pathogenic variants in VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. METHODS: Eighty-nine Japanese patients with clinically suspected VEXAS syndrome were recruited [81 males and 8 females; median onset age (IQR) 69.3 years (62.1-77.6)]. Peptide nucleic acid-clamping PCR (PNA-PCR), regular PCR targeting exon 3 clustering UBA1 variants, and subsequent Sanger sequencing were conducted for variant screening. Partitioning digital PCR (pdPCR) or targeted amplicon deep sequencing (TAS) was also performed to evaluate the variant allele frequency (VAF). We developed our clinical scoring system to predict UBA1 variant-positive and ­negative patients and assessed the diagnostic value of our system using receiver operating characteristic (ROC) curve analysis. RESULTS: Forty patients with reported pathogenic UBA1 variants (40/89, 44.9%) were identified, including a case having a variant with VAF of 1.7%, using a highly sensitive method. Our clinical scoring system considering >50 years of age, cutaneous lesions, lung involvement, chondritis, and macrocytic anaemia efficiently predicted patients with UBA1 variants (the area under the curve for the scoring total was 0.908). CONCLUSIONS: Genetic screening with the combination of regular PCR and PNA-PCR detected somatic UBA1 variants with high sensitivity and specificity. Our scoring system could efficiently predict patients with UBA1 variants.

Late-Onset Systemic Lupus Erythematosus Associated with Autoimmune Hemolytic Anemia and Sixth Cranial Nerve Palsy.

BACKGROUND Patients with late-onset systemic lupus erythematosus (SLE) do not present with typical SLE symptoms or serology, and this can lead to a major delay in diagnosis. We report a complex case of an older woman who developed autoimmune hemolytic anemia and sixth cranial nerve palsy that posed considerable challenges in diagnosing late-onset SLE. CASE REPORT A 78-year-old Japanese woman presented with polyarthritis associated with generalized fatigue for 2 months, who later developed diplopia. Physical examination revealed conjunctival pallor, polyarthritis, and subsequent development of sixth cranial nerve palsy. Laboratory data revealed a decreased white blood cell count; macrocytic anemia; elevated levels of lactate dehydrogenase, indirect bilirubin, and erythrocyte sedimentation rate; hypocomplementemia; positive Coombs test; antinuclear antibodies (ANAs, 1: 40); and positive anti-double-strand DNA antibodies. Lymphoma, cerebral venous sinus thrombosis, and varicella-zoster virus infection were unlikely based on head computed tomography, brain magnetic resonance imaging, and cerebrospinal fluid analysis. She was diagnosed with late-onset SLE associated with autoimmune hemolytic anemia and sixth cranial nerve palsy. The patient was successfully treated with prednisone and hydroxychloroquine. CONCLUSIONS The difficulty in diagnosing late-onset SLE with atypical presentations and uncommon complications must be recognized. SLE cannot be excluded based on a low titer of ANA in a particular subgroup such as the elderly, and the prozone effect should be considered responsible for low ANA titers. In this case, late-onset SLE was diagnosed by considering multisystem pathologies despite low ANA titers.

Unusual organ involvement in sarcoidosis: sarcoid myopathy and peritoneal sarcoidosis.

Myopathy and peritoneal involvement are rare complications of sarcoidosis, and the latter can mimic malignancy with peritoneal dissemination. In this case, a patient with a history of polyarthritis and positive rheumatoid factor presented with proximal muscle weakness and abdominal pain. Biopsies of muscle and peritoneum revealed non-caseating granuloma suggesting sarcoidosis. Ocular and pulmonary involvement later developed and confirmed the diagnosis of sarcoidosis.

Postpartum pheochromocytoma-induced takotsubo syndrome.

A postpartum patient with acute-onset dyspnoea and hypotention, associated with reduced left ventricular function requiring intensive blood pressure control, was initially misdiagnosed as having peripartum cardiomyopathy. Her clinical symptoms rapidly resolved. Echocardiography revealed reversible left ventricular dysfunction with apical ballooning and coronary angiography was normal. Based on these findings, we diagnosed takotsubo syndrome. Over the next two months, the patient experienced repeated bouts of elevated sympathetic activity. On workup, we found an adrenal mass and elevated urine metanephrines. After adrenalectomy, histology confirmed pheochromocytoma. Our patient had the rare diagnosis of postpartum pheochromocytoma-induced takotsubo syndrome.

Bilateral calcified ureteral stenosis in eosinophilic granulomatosis with polyangitis.

Ureteral calcification is a rare complication of systemic vasculitis. Bilateral ureteral calcification in a patient with eosinophilic granulomatosis with polyangitis led to obstructive uropathy. A combination of immunosuppressive therapy and ureteral reconstruction successfully restored kidney function.