A previously healthy 21-month-old Pakistani girl presented to our institution in June 2025 with a 1-year history of a pruritic papulovesicular rash affecting her limbs and groin. Apart from intermittent viral illnesses, there were no reported episodes of abdominal pain, vomiting or other symptoms suggestive of acute pancreatitis. She had been thriving well with normal intake, urine output and bowel habit. She was born at term by vaginal delivery with an uneventful perinatal history. Her parents were healthy second cousins.

Physical examination of the patient revealed multiple discrete yellow papules over all four limbs and the groin, sparing the face, trunk and back. Otherwise, she appeared well with age-appropriate growth parameters.

Two months prior to the current presentation, the patient had been admitted with an upper respiratory tract infection. Laboratory investigations showed mild microcytic anaemia, but routine biochemistry was unremarkable. The chemical pathology report noted serum turbidity requiring clearance by high-speed centrifugation prior to non-lipid analysis; however, this critical finding was overlooked, and the patient was discharged home.

At the latest clinic visit, the skin lesions were recognised as eruptive xanthomas, appearing as small yellow papules with a creamy centre (Fig 1). A grossly lipaemic blood sample showed a thick creamy layer (Fig 2), raising clinical suspicion of severe hypertriglyceridaemia. Laboratory testing confirmed this, with triglyceride level measuring 100.6 mmol/L.

The patient was admitted to the paediatric intensive care unit, kept nil by mouth and commenced on intravenous Actrapid (Bagsværd, Denmark) 0.1 unit/kg/hr, with a dextrose infusion to maintain euglycaemia. After 43.5 hours of infusion therapy, triglyceride level had reduced to 1.3 mmol/L (Fig 3). Following intravenous insulin therapy, she was managed with dietary restriction and essential fatty acid supplementation. Throughout the course, serial amylase and lipase levels remained normal. Computed tomography excluded acute pancreatitis. A family history revealed a nephew with monogenic hypertriglyceridaemia due to a GPIHBP1 mutation, which was subsequently confirmed in our patient.

Monogenic hypertriglyceridaemia, also known as type I hyperlipidaemia, is an uncommon autosomal recessive condition most often resulting from LPL gene mutations that impair lipoprotein lipase function.1 The disorder usually manifests in childhood with recurrent abdominal pain, pancreatitis, or characteristic features such as eruptive xanthomas, lipaemia retinalis, and hepatosplenomegaly. Without appropriate management, recurrent pancreatitis may progress to chronic disease with subsequent exocrine and endocrine insufficiency. Clinical manifestations typically emerge before 10 years of age, and approximately one quarter of cases present within the first year of life.2

Acute pancreatitis typically arises when serum triglyceride concentrations exceed 11.3 mmol/L.3 4 Management involves fasting, intravenous fluid support, and continuous insulin infusion. This activates lipoprotein lipase, accelerating triglyceride clearance—reducing levels within 24 hours by approximately 40% with insulin alone and up to 80% when combined with fasting.5 Despite this, some individuals, as in our case, remain asymptomatic even with extreme hypertriglyceridaemia.6 In retrospect, earlier recognition of these ‘creamy’ clues—eruptive xanthomas and lipaemic serum—could have enabled a timelier diagnosis of this rare lipid disorder.

Concept or design: A Fu.
Acquisition of data: Both authors.
Analysis or interpretation of data: Both authors.
Drafting of the manuscript: A Fu.
Critical revision of the manuscript for important intellectual content: A Fu.

Both authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

Both authors have disclosed no conflicts of interest.

The authors thank Dr Doris Ching and her team from the Department of Chemical Pathology, Princess Margaret Hospital for their unwavering support in facilitating the molecular diagnosis of the patient.

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The patient was treated in accordance with the Declaration of Helsinki. The parents of the patient provided written consent for all treatments and procedures, and verbal consent for publication, including the publication of the accompanying clinical images.

1. Chyzhyk V, Brown AS. Familial chylomicronemia syndrome: a rare but devastating autosomal recessive disorder characterized by refractory hypertriglyceridemia and recurrent pancreatitis. Trends Cardiovasc Med 2020;30:80-5. Crossref

2. Mustafa M, Almheiri M. Six-year follow-up of a child with familial chylomicronemia syndrome: disease course and effectiveness of gemfibrozil treatment—case report and literature review. Ann Pediatr Endocrinol Metab 2024;29:130-4. Crossref

3. Krishnamurthy A, Homan E, Kim SM. Diagnosis, evaluation, and management of severe hypertriglyceridemia. Curr Cardiovasc Risk Rep 2025;19:6. Crossref

4. Valaiyapathi B, Ashraf AP. Hospital management of severe hypertriglyceridemia in children. Curr Pediatr Rev 2017;13:225-31. Crossref

5. Witztum JL, Gaudet D, Freedman SD, et al. Volanesorsen and triglyceride levels in familial chylomicronemia syndrome. N Engl J Med 2019;381:531-42. Crossref

6. Schaefer EW, Leung A, Kravarusic J, Stone NJ. Management of severe hypertriglyceridemia in the hospital: a review. J Hosp Med 2012;7:431-8. Crossref

A 33-year-old primiparous Chinese woman presented for a 12-week ultrasound. Previous early ultrasound had confirmed monochorionic diamniotic twins. Her marriage was non-consanguineous. She had conceived spontaneously and had no family history of inborn errors of metabolism. The 12-week fetal scan revealed normal nuchal translucency in both twins, and non-invasive prenatal testing showed normal results.

Serial ultrasound examinations were performed every 2 weeks from 16 weeks onwards to monitor fetal growth and detect early signs of twin-twin transfusion syndrome or twin anaemia-polycythaemia sequence. Both fetuses followed the 10th percentile growth curve in abdominal circumference, head circumference, and femur length. Morphology scan showed no abnormalities, and there was no evidence of twin-twin transfusion syndrome or twin anaemia-polycythaemia sequence throughout the pregnancy. Routine targeted neurosonography at 32 weeks showed multiple bilateral germinolytic cysts and temporal cysts in both fetuses (Fig). Brain findings were almost identical in both twins. Although abdominal circumference and femur length remained at the 10th percentile, the head circumference of Fetus A exceeded more than two standard deviations above the mean, while that of Fetus B was at the mean. Fetal magnetic resonance imaging (MRI) at 33 weeks demonstrated normal brain structure with cystic findings consistent with the ultrasound findings and no signs of ischaemia. Amniocentesis at 34 weeks for chromosomal microarray and cytomegalovirus polymerase chain reaction tests yielded negative results. Trio whole-genome sequencing was arranged. At 35 weeks, the mother developed pre-eclampsia, and an emergency lower-segment Caesarean section was performed the following day. Whole-genome sequencing results, available on the day of delivery, revealed a homozygous pathogenic variant, c.1244-2A>C, in the GCDH gene (NM_000159.4) associated with glutaric aciduria type 1 (GA1). Both parents were found to be heterozygous carriers of this variant. Fetus A weighed 2.4 kg with Apgar scores of 7 at 1 minute and 8 at 5 minutes, while Fetus B weighed 2.2 kg and had Apgar scores of 9 at 1 minute and 10 at 5 minutes. Umbilical cord arterial pH was 7.35 for Fetus A and 7.29 for Fetus B. Both neonates were admitted to the neonatal unit and promptly started on intravenous L-carnitine supplementation and a specialised formula diet. No seizures have been observed to date. Postnatal brain MRI at 1 month of age showed unchanged cystic findings in both twins, with no evidence of white matter involvement.

This case highlights the importance of comprehensive prenatal evaluation, including detailed neurosonography and fetal brain MRI, when unusual fetal brain findings are detected. The initial concern was for transfusion-related complications; however, the absence of typical features prompted a broader differential diagnosis, ultimately leading to the diagnosis of GA1. Metabolic crises such as severe hypoglycaemia, hyperammonaemia, lactic acidosis, and permanent neurological or systemic complications can occur in patients diagnosed after the onset of symptoms. Early identification of GA1 enabled prompt multidisciplinary consultation and the initiation of appropriate treatment, including dietary management. Prenatal diagnosis of GA1 based on third-trimester brain features is possible and facilitates early postnatal management, enabling prompt treatment at birth and potentially improving long-term neurological outcomes.

Concept or design: IYM Wah.
Acquisition of data: All authors.
Interpretation of data: All authors.
Drafting of the manuscript: IYM Wah.
Critical revision of the manuscript for important intellectual content: All authors.

All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

All authors have disclosed no conflicts of interest.

The authors thank the Obstetrics and Gynaecology team, Maternal Fetal Medicine team, midwives, scientists, genetic counsellor and paediatricians at Prince of Wales Hospital for their support in managing the case.

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The patient was treated in accordance with the Declaration of Helsinki. Written informed consent was obtained from the patient for publication of the details of the medical case and the accompanying images.

Dental examination remains an important step before the prescription of antiresorptive medication for osteoporosis. Antiresorptive medication may result in osteonecrosis of the jaw.1 Invasive dental procedures may require interruption of these medications, and the procedure itself may result in osteonecrosis if patients are concurrently taking them.1 Dental examination should include identification of obvious dental caries and periodontal disease. We report a case of an unusually large dental calculus in an older adult, highlighting the importance of routine dental examination, particularly in this population.

A 92-year-old man was admitted to our institution in March 2025 with vertebral fractures at the 1st lumbar and 12th thoracic vertebrae. Past medical history included minor stroke, hypertension, gout and atrial fibrillation for which the patient was prescribed an oral anticoagulant. Physical examination revealed no neurological deficit. Dual energy X-ray absorptiometry had not previously been performed. Examination of the oral cavity, performed before prescribing antiresorptive medication, revealed a 3-cm yellowish-white, calcified mass on the lower gingiva (Fig a). No teeth were seen in the oral cavity. The tooth to which the calculus might have been attached could not be identified. The deposit had been present for over 20 years, but the patient had not sought dental evaluation. X-ray revealed an oval-shaped calcified mass near the mandible (Fig b). Microscopic examination of the scraped lesion showed calcified foreign materials admixed with bacterial microorganisms and benign epithelial cells. A speech therapist was consulted and reported no dysphagia related to the calculus. The patient was referred to the dentist for extraction and to exclude malignancy, although he and his relatives were indecisive. Antiresorptive medication was not prescribed. He was prescribed a calcium and a vitamin D supplement.

Dental calculus is a calcified deposit that forms on teeth and other oral structures when plaque hardens over time.2 3 4 Often it is related to poor oral hygiene.2 3 4 Although small amounts of calculus are common, the presence of a large, longstanding deposit is rare and can lead to significant oral and systemic health issues if left untreated. There have been previous case reports of huge dental calculus reported and often extraction is needed to allow complete examination for underlying malignancy.3 4 Prominent calculus impairs mastication and increases the risk of periodontal disease, limiting food choices and increasing the risk of malnutrition and sarcopenia.2 In addition, the potential need for invasive dental procedures will preclude the early prescription of antiresorptive agents.

Previously, there were concerns about the provision of non-urgent public dental services for older adults in Hong Kong.5 With the provision of an electronic booking system, the Community Care Fund Elderly Dental Assistance Programme and the Elderly Health Care Voucher Scheme, it is hoped that older adults will have improved access to local non-emergent dental services.5

This case underscores the need for dental examination in older adults before starting antiresorptive medication.

Both authors contributed equally to the concept or design, acquisition of data, analysis or interpretation of data, drafting of the manuscript, and critical revision of the manuscript for important intellectual content. Both authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

Both authors have disclosed no conflicts of interest.

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The patient was treated in accordance with the Declaration of Helsinki. Informed consent was obtained from the patient for all treatments and procedures. The patient also provided written consent for publication of this case report with the accompanying images.

1. OSHK Task Group for the Formulation of the 2024 OSHK Guideline for Clinical Management of Postmenopausal Osteoporosis in Hong Kong; Ip TP, Lee CA, et al. 2024 OSHK Guideline for Clinical Management of Postmenopausal Osteoporosis in Hong Kong. Hong Kong Med J 2024;30 Suppl 2:1-44.

2. Azzolino D, Passarelli PC, De Angelis P, Piccirillo GB, D'Addona A, Cesari M. Poor oral health as a determinant of malnutrition and sarcopenia. Nutrients 2019;11:2898. Crossref

3. Chauhan Y, Jain S, Ratre MS, Khetarpal S, Varma M. Giant dental calculus: a rare case report and review. Int J Appl Basic Med Res 2020;10:134-6. Crossref

4. Woodmansey K, Severine A, Lembariti BS. Giant calculus: review and report of a case. Gen Dent 2013;61:e14-6.

5. Shea YF, Shum CK, Lee SW. Urgent need to improve dental services for older adults in Hong Kong. Asian J Gerontol Geriatr 2024;19:5-7. Crossref

A 72-year-old man with recurrent hepatitis B virus–related hepatocellular carcinoma was referred for right portal vein embolisation (PVE) prior to right hepatectomy. He had Child-Pugh class A cirrhosis, with calculated indocyanine green–R15 of 8%. Portal embolisation was indicated due to the presence of multiple co-morbidities and marginal future liver remnant volume of 35%.

Preprocedural computed tomography revealed duplication of the portal vein (DPV) [Fig 1]. The anatomy and feasibility of the procedure was discussed with hepatic surgeons. Right PVE was successfully performed with n-butyl cyanoacrylate glue. Left hepatic lobe hypertrophy from 430 cm³ to 560 cm³ was achieved. The patient subsequently underwent an uneventful right hepatectomy.

Portal vein embolisation is a commonly adopted strategy to induce future liver remnant hypertrophy prior to hepatectomy. Knowledge of the portal venous anatomy and its variants is vital for treatment planning. Duplication of the portal vein is a rare congenital anomaly that has been described only in case reports. It is related to the spectrum of vitelline vein regression anomaly with pathogenesis believed to be failed regression of the left cranial part of the vitelline vein (Fig 2a-e).1 A variation of DPV has been reported; some authors describe two portal veins arising separately without extrahepatic communications,2 while some describe an additional portal vein arising anomalously from either the superior mesenteric vein or the splenic vein (Fig 2f-i).3 The latter was evident in our patient (Fig 1).

Another anomaly with double channel portal vein is portal vein fenestration in which there is a small fenestration at the mid portion of the main portal vein.4 The exact pathogenesis and its relationship with portal vein duplication remains unknown.

In the presence of DPV, there was altered flow dynamic with preferential opacification of the right or left portal vein branches depending on different catheter tip positions (Fig 3). There was preferential flow towards the left portal branches at the intrahepatic communication at the hepatic hilum, giving a narrow safety margin for embolisation to prevent non-target embolisation of the left portal vein that could jeopardise the future liver remnant.

Our patient successfully underwent PVE without complication. The degree of hypertrophy was similar to that reported in local cohorts.5 Surgeons discussed whether the anomalous portal vein could be embolised to improve the efficacy of PVE but there was also a risk of jeopardising venous return from small branches of the superior mesenteric vein that may worsen liver function.

During hepatectomy, DPV was confirmed (Fig 4). It did not affect surgical planning and the patient underwent right hepatectomy uneventfully.

Duplication of the portal vein is a rare congenital anomaly. Because of the possible altered flow dynamics, it is important to identify this anomaly on preprocedural imaging and arrange multidisciplinary team discussion to plan PVE and ensure a safe and effective procedure.

Concept or design: All authors.
Acquisition of data: All authors.
Analysis or interpretation of data: OL Chan, YS Lee.
Drafting of the manuscript: OL Chan, YS Lee.
Critical revision of the manuscript for important intellectual content: All authors.

All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

All authors have disclosed no conflicts of interest.

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

This study was approved by the Central Institutional Review Board of Hospital Authority, Hong Kong (Ref No.: CIRB-2023-064-1). Written informed consent was obtained from the patient for publication of this article.

1. Qin Y, Wen H, Liang M, et al. A new classification of congenital abnormalities of UPVS: sonographic appearances, screening strategy and clinical significance. Insights Imaging 2021;12:125. Crossref

2. Dighe M, Vaidya S. Case report. Duplication of the portal vein: a rare congenital anomaly. Br J Radiol 2009;82:e32-4. Crossref

3. Kitagawa S. Anomalous duplication of the portal vein with prepancreatic postduodenal portal vein. J Rural Med 2022;17:259-61. Crossref

4. Balradja I, Har B, Rastogi R, Agarwal S, Gupta S. Portal vein fenestration: a case report of an unusual portal vein developmental anomaly. Korean J Transplant 2022;36:298-301. Crossref

5. Yu KC, Wong SS, Wong YC, et al. Procedure time, efficacy, and safety of portal vein embolisation using a sheathless needle-only technique compared with traditional technique. Hong Kong J Radiol 2022;25:35-44. Crossref

A 67-year-old female was admitted to the neurology department in October 2020 with abnormal behaviour and cognitive impairment. Her memory and numeracy had declined, and symptoms progressed over the preceding week. She had a 30-year history of chronic alcohol abuse with an average daily intake of 500-mL liquor.

Routine biochemistry including electrolytes, liver function, and vitamin B12 were within normal limits. Magnetic resonance imaging of the brain showed areas of hyperintensity of the corpus callosum (splenium, body, and genu), bilateral middle cerebellar peduncles, periventricular white matter, and subcortical white matter of the frontal lobe on T2-weighted and fluid-attenuated inversion recovery images. Diffusion-weighted imaging revealed prominent high-intensity signal lesions involving the splenium, and these corresponding lesions were hypointense on the apparent diffusion coefficient map (Fig). Based on her history, physical examination and magnetic resonance imaging features, the patient was diagnosed with Marchiafava–Bignami disease (MBD). Despite a normal level of serum vitamins, the patient was prescribed vitamin B and neurotrophic treatment. Symptoms improved and she made a good recovery over the next 30 days.

Marchiafava–Bignami disease is a rare neurological syndrome characterised by primary degeneration and necrosis of the corpus callosum associated with chronic alcoholism and malnutrition. The clinical manifestations of MBD are severe and nonspecific and include an altered mental state, impaired walking, deficient memory, and dysarthria. Symptoms and imaging findings may improve following thiamine treatment.1 2 The role of magnetic resonance imaging is essential to confirm the diagnosis. Chronic alcohol abuse plays an important role in its development although MBD has been occasionally diagnosed in patients with no history of alcohol abuse, in particular individuals with poorly controlled diabetes mellitus or following surgery.3 4 The aetiology and pathophysiology of MBD remain unclear. Possible mechanisms include cytotoxic oedema, blood-brain barrier breakdown, demyelination, and necrosis. Early pathological manifestations are mainly intramyelinic or cytotoxic oedema. In the later stages, demyelination and necrosis of the corpus callosum (especially in the genu and the body) may follow5 with necrosis leading to atrophy and cavitation in chronic stages, and a decreased number of oligodendrocytes. Occasionally, similar lesions can involve extracallosal regions, such as the anterior and posterior commissures, subcortical white matter, middle cerebellar peduncle, optic chiasm, putamen, internal capsules, hippocampus, and frontal cortex.2

The recent advances in neuroradiology techniques help understand the pathophysiological processes of MBD. Studies with diffusion-weighted imaging have shown a low apparent diffusion coefficient, which has been interpreted as irreversible cytotoxic oedema, and may precede the development of demyelination and necrosis and predict a poor or partial recovery.2 5 Nonetheless the high apparent diffusion coefficient showing reversible signal changes favoured an underlying vasogenic oedema-related process. In magnetic resonance spectroscopy studies, an increased choline/creatine ratio indicates demyelination during the acute phase of MBD, while a reduced N-acetylaspartate/creatine ratio suggests secondary axonal injury. In addition, decreased cerebral blood flow and cerebral blood volume in magnetic resonance perfusion suggest hypoperfusion. Recognition of the neuroradiological features is crucial to establish a diagnosis.

Concept or design: Both authors.
Acquisition of data: Q Wang.
Analysis or interpretation of data: F Ren.
Drafting of the manuscript: F Ren.
Critical revision of the manuscript for important intellectual content: Q Wang.

Both authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

Both authors have disclosed no conflicts of interest.

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

This study was approved by the Hospital of Chengdu University of Traditional Chinese Medicine Research Ethics Committee, China. Informed consent for all treatments and procedures, and consent for publication were obtained from the patient.

1. Tsai CY, Huang PK, Huang P. Simultaneous acute Marchiafava–Bignami disease and central pontine myelinolysis: a case report of a challenging diagnosis. Medicine (Baltimore) 2018;97:e9878. Crossref

2. Hillbom M, Saloheimo P, Fujioka S, Wszolek ZK, Juvela S, Leone MA. Diagnosis and management of Marchiafava–Bignami disease: a review of CT/MRI confirmed cases. J Neurol Neurosurg Psychiatry 2014;85:168-73. Crossref

3. Pérez Álvarez AI, Ramón Carbajo C, Morís de la Tassa G, Pascual Gómez J. Marchiafava–Bignami disease triggered by poorly controlled diabetes mellitus [in English, Spanish]. Neurologia 2016;31:498-500. Crossref

4. Bachar M, Fatakhov E, Banerjee C, Todnem N. Rapidly resolving nonalcoholic Marchiafava–Bignami disease in the setting of malnourishment after gastric bypass surgery. J Investig Med High Impact Case Rep 2018;6:2324709618784318. Crossref

5. Ménégon P, Sibon I, Pachai C, Orgogozo JM, Dousset V. Marchiafava–Bignami disease: diffusion-weighted MRI in corpus callosum and cortical lesions. Neurology 2005;65:475-7. Crossref