Cutaneous nodules and a novel GNAS mutation in a Chinese boy with pseudohypoparathyroidism type Ia: A case report and review of literature

Characterizing Cerebral Imaging and Electroclinical Features of Five Pseudohypoparathyroidism Cases Presenting with Epileptic Seizures

Objective

To characterize the cerebral imaging and electroclinical features and investigate their etiological contributions to seizures in pseudoparathyroidism (PHP).

Methods

The clinical symptoms, biochemical imaging by magnetic resonance imaging (MRI) and computed tomography (CT) tests, and electroencephalogram (EEG) manifestations of five PHP patients with seizures were retrospectively collected and analyzed.

Results

Physical examination showed an average stature in cases 2~4 and short stature in cases 1 and 5. X-ray tests suggested ectopic calcification in four patients. The seizures in four cases were effectively controlled with antiseizure medicines (ASMs). Cerebral CT scans showed extensive brain calcifications in the bilateral basal ganglia (all five cases), cerebellum (cases 1, 3, and 5), thalamus (case 4), and cerebral cortex. Cerebral MRI showed short T1 signals mainly in the basal ganglia. EEG records revealed focal EEG abnormalities, including abnormal slow waves and epileptiform discharges, mainly over the temporal and frontal lobes. The brain areas with focal EEG abnormalities and calcification did not always coincide.

Conclusion

The seizures in PHP can be focal to bilateral tonic–clonic. ASMs are effective in epilepsy combined with PHP. Intracranial calcification is not a reliable etiological cause of epilepsy in PHP patients.

Response to trametinib in a nonsmall cell lung cancer patient with osimertinib resistance harboring GNAS R201C and R201H mutations: a case report

Osimertinib, an orally administered third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is widely approved for the first-line and second-line treatment of advanced non-small-cell lung cancer (NSCLC) with EGFR mutations. However, the rapid development of osimertinib resistance renders the unsustainable treatment benefit. Patients with EGFR-mutated NSCLC who develop osimertinib resistance, especially those acquiring relatively rare and 'off-target' resistance mutations, still lack effective therapeutic options for postosimertinib therapy. Herein, we reported a 73-year-old woman diagnosed with T1N3M1 lung adenocarcinoma harboring EGFR L858R mutation, who acquired two GNAS mutations (R201C and R201H) and lost the EGFR L858R mutation after progression on icotinib and osimertinib. The patient was subsequently treated with trametinib and there was no obvious tumor increase. Our study revealed that GNAS R201 can confer the osimertinib resistance in EGFR-positive NSCLC, and present the first report of the prevalence of GNAS R201C and R201H mutants in NSCLC which response to trametinib treatment. Our case suggests that trametinib could be a treatment option in NSCLC patients harboring GNAS-activating mutations.

Early Diagnosis of Pseudohypoparathyroidism before the Development of Hypocalcemia in a Young Infant

Pseudohypoparathyroidism (PHP) is a rare, heterogeneous disorder characterized by end-organ resistance to parathyroid hormone (PTH). PTH resistance causes elevated PTH levels, hypocalcemia, and hyperphosphatemia. Since hypocalcemia causes life-threatening events, early diagnosis is crucial. However, the diagnosis of PHP is elusive during infancy because PHP is usually diagnosed with hypocalcemia-induced symptoms, which develop later in childhood when calcium requirements increase. A 1-month-old girl was referred to our clinic for elevated thyroid-stimulating hormone (TSH) levels on newborn screening. When measured 1 month after levothyroxine treatment, her TSH level normalized. At 4-months-old, multiple hard nodules were noted on her trunk. A punch skin biopsy revealed osteoma cutis associated with Albright’s hereditary osteodystrophy, a major characteristic of PHP. We performed targeted sanger sequencing of the GNAS gene and detected a heterozygous variant c.150dupA (p.Ser51Ilefs*3) in both the proband and her mother, causing frameshift and premature termination mutations. The patient was diagnosed with PHP Ia when she had normal calcium, phosphorous, and PTH levels. We report the early diagnosis of PHP Ia without hypocalcemia. It emphasizes the importance of meticulous physical examination in patients with congenital hypothyroidism.