Oncogenic Osteomalacia: Challenges in Diagnosis.

To report a case of osteomalacia induced by a mesenchymal tumour in the head and neck region, in view of its rarity and classical late diagnosis. To review the literature on the usage of fluorodeoxyglucose-positron emission tomography-computed tomography (FDG PET-CT) and octreotide scanning in the localisation of the culprit tumour. An elderly male presented with a 7-year history of chronic muscle pain and weakness, to the extent of functional disability. FDG PET-CT was done which showed uptake in the region of the right anterior ethmoids. Endoscopic excision of the mass was done. However, the patient did not improve significantly. Subsequently, a DOTA-1-NaI3-octreotide (DOTANOC) scan was done which revealed a tumour in the region of the right medial rectus, excision of which was done. This time, the patient improved clinically and biochemically. The histopathology was phosphaturic mesenchymal tumour. A steady but definitive symptomatic improvement was noted in the postoperative period along with reversal of the deranged biochemical parameters, confirming the diagnosis of oncogenic osteomalacia. Octreotide-based PET-CT seems to be the most sensitive imaging modality in localising the tumours that cause oncogenic osteomalacia. However, FDG-based PET-CT still would be a good choice in centres where SSTR-based imaging facilities are not available.

An Interesting Case of Thyrotoxicosis.

Ectopic thyroid tissue can be present in the embryonal path of descent of the thyroglossal duct anywhere from the foramen caecum to the thyroid gland. However, for such ectopic thyroid tissue to be hyperfunctioning is quite rare. Here, we discuss a 56-year-old female patient who presented with persistent thyrotoxicosis for over 7 years. She had undergone thyroidectomy in 1982 for thyrotoxicosis and was rendered hypothyroid (thyroid-stimulating hormone of 75 µIU/mL). Whole-body technetium scan was done twice which did not show any uptake in the neck or other parts of the body and an empirical dose of 15 mCi of radioiodine therapy was also given to treat the thyrotoxicosis. She continued to be thyrotoxic and was on carbimazole 30 mg/day along with beta-blockers. In 2021, an Iodine131 whole-body scan revealed small remnant thyroid tissue and an ectopic thyroid tissue in a thyroglossal cyst. In such cases of persistent or recurrent thyrotoxicosis despite standard treatments, an ectopic location should be sought after and treated.

Multimodal Imaging and Visual Evoked Potentials Reveal Key Structural and Functional Features That Distinguish Symptomatic From Presymptomatic Huntington's Disease Brain.

BACKGROUND: Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by motor, cognitive, and psychiatric abnormalities. Currently, matched analyses of structural and functional differences in the brain from the same study cohort and, specifically, in HD patients from an ethnically diverse Indian population are lacking. Such findings aid in identifying noninvasive and sensitive imaging biomarkers. OBJECTIVE: The aim of the study was to understand the structural and functional differences between HD and control brain, and presymptomatic and symptomatic HD brain in the Indian population. MATERIALS AND METHODS: Seventeen HD (11 symptomatic HD [S-HD] and six presymptomatic HD [P-HD], with comparable CAG repeats), and 12 healthy controls were examined. Macrostructural (volume), microstructural (diffusivity), and functional (neurochemical levels and glucose metabolism) imaging of the brain was done along with the determination of visual latencies. RESULTS: HD brain showed increased intercaudate distance; significant subcortical volumetric loss; reduced fractional anisotropy; increased mean, axial, and radial diffusivity; lower levels of total N-acetyl aspartate; elevated total choline levels; and reduced glucose metabolism compared with control brain. Interestingly, compared with P-HD, S-HD patients demonstrated a strong inverse correlation between age at onset and CAG repeat length, and prolonged P100 latency. In addition, caudate and putamen in S-HD brain showed significant volumetric loss and increased diffusivity compared with P-HD brain. CONCLUSIONS: HD brain showed distinct macrostructural, microstructural, and functional differences compared with control brain in the Indian population. Interestingly, patients with S-HD had a significant volumetric loss, increased diffusivity, altered neurochemical profile, and delayed P100 latency compared with P-HD patients. Examining these alterations clinically could aid in monitoring the progression of HD.

Melioidosis Presenting as Septic Arthritis: The Role of F-18 Fludeoxyglucose Positron Emission Tomography/Computed Tomography in Diagnosis and Management.

Melioidosis, caused by the soil saprophyte Burkholderia pseudomallei, is a great mimicker. With its wide variety of presentations which are often nonspecific, a good clinical suspicion is required for the timely diagnosis of the disease. F-18 fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) has a well-established role in the diagnosis and management of various infective diseases. Given the multifocal nature of this disease, we believe that F-18 FDG PET/CT has a definite role in improving the management of melioidosis. Here, we discuss a case of melioidosis presenting as septic arthritis and the role of F-18 FDG PET/CT in the management of the disease.

Radio-guided Minimally Invasive Parathyroidectomy: A Descriptive Report of the Experience from Tertiary Center in Bangalore.

OVERVIEW: Minimally invasive parathyroidectomy (MIP) is an accepted surgical procedure for parathyroid adenomas. In the patients with parathyroid adenoma localized by dual phase 99mTc-Sestamibi scan, a focused approach utilizing the gamma probe intra-operatively helps in ensuring complete resection and avoiding exploration of the other parathyroid glands. OBJECTIVE: The aim of the study was to evaluate the performance of radio-guided MIP for parathyroid adenomas detected by dual phase 99mTc-MIBI preoperatively, without intra-operative parathyroid hormone (ioPTH) monitoring for patients who had evidence of single-gland disease. PATIENTS AND METHODS: A retrospective dataset of 30 patients diagnosed with solitary parathyroid adenoma operated between 2009 and 2014 were reviewed. All of the patients underwent radio-guided MIP and were followed up for at least 6 months post-operatively. The biochemical parameters (serum calcium and serum parathyroid hormone levels), imaging parameters (ultrasonography and 99mTc-MIBI), and operative times were analyzed. RESULTS: Our study consisted of 30 patients with 50% females, with a mean age of 42.5 + 12 years. The mean surgical duration was 20 + 12 min. All of the patients achieved biochemical cure (normalization of serum calcium) and remained eucalcemic at follow-up. No major surgical complications were noted. CONCLUSIONS: Focused parathyroidectomy using the gamma probe localization could be a potential alternative for ioPTH assay in ensuring the completeness of surgical resection of parathyroid adenoma. It is also likely to shorten operative time.