Severe NAD(P)HX Dehydratase (NAXD) Neurometabolic Syndrome May Present in Adulthood after Mild Head Trauma.

We have previously reported that pathogenic variants in a key metabolite repair enzyme NAXD cause a lethal neurodegenerative condition triggered by episodes of fever in young children. However, the clinical and genetic spectrum of NAXD deficiency is broadening as our understanding of the disease expands and as more cases are identified. Here, we report the oldest known individual succumbing to NAXD-related neurometabolic crisis, at 32 years of age. The clinical deterioration and demise of this individual were likely triggered by mild head trauma. This patient had a novel homozygous NAXD variant [NM_001242882.1:c.441+3A>G:p.?] that induces the mis-splicing of the majority of NAXD transcripts, leaving only trace levels of canonically spliced NAXD mRNA, and protein levels below the detection threshold by proteomic analysis. Accumulation of damaged NADH, the substrate of NAXD, could be detected in the fibroblasts of the patient. In agreement with prior anecdotal reports in paediatric patients, niacin-based treatment also partly alleviated some clinical symptoms in this adult patient. The present study extends our understanding of NAXD deficiency by uncovering shared mitochondrial proteomic signatures between the adult and our previously reported paediatric NAXD cases, with reduced levels of respiratory complexes I and IV as well as the mitoribosome, and the upregulation of mitochondrial apoptotic pathways. Importantly, we highlight that head trauma in adults, in addition to paediatric fever or illness, may precipitate neurometabolic crises associated with pathogenic NAXD variants.

A radiological severity scale to measure the impact of Charcot's Neuroarthropathy: an observational study.

BACKGROUND: Charcot's Neuroarthropathy (Charcot foot) is a debilitating and destructive disorder resulting from neurological changes in the foot. Whilst the majority of cases are painless, as a result of disruption to sensory function, a common outcome is severe deformity that impacts considerably on foot function. The purpose of this study was to develop and validate a radiological severity scale to quantify resultant damage from acute mid foot Charcot's. This in turn can be used to evaluate clinical outcomes related to different degrees of offloading. METHODS: A four round Delphi process was used to develop five tool items. Level of consensus and agreement was set at 80%. Inter-rater and intra-rater reliability was evaluated using 3 raters and 24 plain x-rays of chronic mid-foot Charcot's. Strength of agreement of individual items and overall scores was calculated using weighted Kappa coefficients (S.E). Cronbach's α was used to determine internal consistency. Floor (> 15% score 0) and ceiling (> 15% score 11) effects were examined at each time point. Spearman's correlation coefficient was used to assess construct validity using Mobility and Usual Activity scores taken from the EQ-5D-5 L. RESULTS: Twenty two patients participated. The five item severity scale demonstrated a Cronbach's α of 0.91. Intra-rater Kappa coefficients (SE) for total scores ranged from 0.84 (0.20) to 0.86 (0.20). Inter rater coefficients (SE) ranged from 0.72 (0.14) to 0.83 (0.14). Distribution was normal and no floor or ceiling effects were identified. CONCLUSION/INTERPRETATION: This study suggests it may be possible to quantify resultant damage from mid foot Charcot's. Given the physical and emotional impacts from long periods of complete immobilisation defining a minimum standard would be an important development in the management of Charcot foot.

Imaging assessment of rounded atelectasis: A pictorial essay.

Rounded atelectasis is an increasingly recognized but under-diagnosed and sometimes misdiagnosed pulmonary entity. This pictorial essay will present a broad range of examples of rounded atelectasis across different imaging modalities with inclusion of typical and atypical presentations. These examples will highlight imaging features that allow confident diagnosis and those that warrant further management, such as imaging surveillance, alternate imaging or invasive procedures for histological evaluation.

Hibernoma: a rare benign soft tissue tumour resembling liposarcoma.

Hibernoma is a rare benign soft tissue tumour that can mimic a liposarcoma on radiographic imaging. Our case series review illustrates the clinical presentation and radiographic appearances of four patients with histologically confirmed hibernoma. Hibernoma is usually hypointense relative to subcutaneous fat on T 1 weighted MRI and demonstrates partial fat suppression on fat-saturated sequences. Large intratumoral vessels likely support the diagnosis of hibernoma but are not invariably present. Fludeoxyglucose avidity on PET scan is not beneficial in distinguishing hibernoma from soft tissue malignancy because of its inherent, metabolically active property. Owing to the radiographic heterogeneity of hibernoma, it is currently not possible to diagnose hibernoma based on imaging characteristics alone. Given the excellent prognosis of hibernoma with marginal excision alone, an appreciation of the radiographic features is helpful in the appropriate pre-operative workup of soft tissue tumours.

A rare cause of adult ileocolic intussusception: ileal leiomyoma.

Intussusception is a rare condition in adulthood and, unlike in children, is usually caused by an identifiable underlying lesion, most commonly a gastrointestinal tumour. The clinical presentation is non-specific and often there are intermittent symptoms making the diagnosis difficult based solely on history and examination. Plain radiography may reveal signs of bowel obstruction, however, CT is the gold standard to diagnose and localise an intussusception in adults. We present an unusual case of adult ileocolic intussusception caused by an ileal leiomyoma. This case highlights the important radiological findings of intussusception presenting with a high-grade obstruction and discusses the potential causes which should be considered.

Imaging of the spectrum of bony injuries in the diabetic foot: a case series with emphasis on non-Charcot fractures.

Diabetes mellitus is associated with an increased risk of lower limb injuries. Peripheral neuropathy, often associated with diabetes, has been demonstrated to increase the risk of fracture almost two-fold and is associated with complications related to fracture healing. Detection of neuropathy-related foot injury is frequently delayed owing to the paucity of symptoms and low degree of suspicion by the clinician. Early recognition of fracture or bone injury and appropriate treatment are critical in preventing debilitating foot deformity and disability. Therefore, the astute radiologist cognizant of these potential injuries plays an essential role in early diagnosis of bony injuries in the diabetic foot. We present a series of radiological images that depict a range of osseous injuries in the diabetic foot and emphasize the role of the radiologist in early recognition of these abnormalities.

What the radiologist needs to know about Charcot foot.

Charcot neuropathic osteoarthropathy (CN) is a progressive disease affecting the bones, joints and soft tissue of the foot and ankle, most commonly associated with diabetic neuropathy. Patients with diabetes complicated by CN have especially high morbidity, frequency of hospitalisation, and therefore, significant utilisation of expensive medical resources. The diagnosis of early CN can be challenging and is based on clinical presentation supported by various imaging modalities. Imaging is important for the detection of early CN and is useful in monitoring progression and complications of the disease. The later stages of CN are potentially devastating for individuals and present an increasing socioeconomic challenge for health systems. The astute radiologist, particularly in the context of a multidisciplinary team, plays a critical role in diagnosis of the primary disease and its complications. This review article aims to outline the key features of CN, emphasising current clinical and radiologic concepts as an aid for the practising radiologist.

A case of emphysematous osteomyelitis of the midfoot: imaging findings and review of the literature.

Emphysematous osteomyelitis is a rare but potentially fatal condition that must be considered whenever intraosseous gas is identified on imaging. The organisms implicated in most cases of emphysematous osteomyelitis are anaerobes or members of the Enterobacteriaceae family. Significant comorbidities, such as malignancy and diabetes mellitus, frequently predispose to this condition, and high mortality rates have been reported. The radiologist must be aware of the implications of identifying intraosseous gas in order to facilitate early diagnosis and expedite management. We report a unique case of a 58-year-old male with diabetes mellitus who presented with emphysematous osteomyelitis of the midfoot and necrotising fasciitis of the ipsilateral distal lower limb. Specimen cultures in this case revealed a pure growth of Group G Streptococcus.

A case of systemic arterial supply to the right lower lobe of the lung: imaging findings and review of the literature.

Systemic arterialization of the lung without pulmonary sequestration is the rarest form of anomalous systemic arterial supply to the lung. This condition is characterised by an aberrant arterial branch arising from the aorta which supplies an area of lung parenchyma with normal bronchopulmonary anatomy. It is often diagnosed following investigation of an incidental cardiac murmur or based on abnormal imaging, as most patients are asymptomatic or minimally symptomatic. Thoracic computed tomography and computed tomography angiography are generally the most useful diagnostic tests. We present a case of a 22-year old female who was diagnosed with systemic arterial supply to a portion of otherwise normal right lower lobe following investigation of low volume haemoptysis.

Lung-volume controlled computerised tomography in real-life acute severe asthma.

OBJECTIVE: It is not known how airway structure is altered during real-life acute asthma exacerbations. The aim of this study was to examine changes in airway structure during acute asthma exacerbations and at convalescence by using lung-volume controlled high resolution computerised tomography (HRCT). METHODS: Eight subjects with acute asthma exacerbation admitted to hospital were recruited. HRCT was performed within 72 h of admission (n = 8) and repeated after 8 weeks of convalescence (n = 7). Individual airways were carefully matched on acute and convalescent CT data sets for comparisons of airway parameters. A novel methodology was employed for standardisation of lung volumes to permit valid comparisons of lung imaging. Measurements of bronchial cross sectional airway area (Aa) and bronchial luminal area (Ai) for each matched airway were obtained using a validated program. RESULTS: The airway wall thickness was analysed as wall area (WA) calculated as a percentage: WA% = WA/Aa × 100. Wilcoxon signed-rank testing was used to compare acute and convalescent asthma and Spearman's correlation to examine associations. Airway lumen (Ai) areas were similar in both acute and stable asthma phases (6.6 ± 3.1 mm(2) versus 7.2 ± 3.8 mm(2) p = 0.8). However, the airway wall was significantly thickened during acute asthma exacerbations compared to convalescence (62 ± 4% versus 55 ± 7%; p = 0.01). There was no correlation between airway structure dimensions and lung function measurements. CONCLUSIONS: This is the first study to demonstrate an increase in airway wall thickness during real-life acute asthma exacerbation. However, narrowing of the airway lumen area was variable and will require larger studies able to detect small differences. These results suggest that airway wall thickening linked to mucosal inflammation is likely to characterise acute asthma in vivo but that changes in the airway lumen accompanying bronchoconstriction may be more heterogeneous.

MR imaging of meniscal and cartilage injuries of the knee.

This article addresses the role of MR imaging in the evaluation of meniscal injuries, with emphasis placed on the common meniscal injuries, including horizontal, longitudinal, radial, and flap tears. An understanding of typical meniscal postoperative findings, together with those factors responsible for the misinterpretation of meniscal abnormalities, is essential for the accurate assessment of MR imaging in the athlete. This article also reviews the common articular cartilage injuries identified in the knee. MR imaging is the imaging modality of choice for the assessment of the menisci and articular cartilage, with the ready availability of MR imaging allowing for the rapid assessment of the injured athlete.

Extramedullary fat fluid level on MRI as a specific sign for osteomyelitis.

The role of MR in the early diagnosis of acute osteomyelitis is well known. In the context of florid cellulitis, abnormalities of marrow signal are not uncommon, although they are often non-specific. Marrow oedema and enhancement in the context of deep cellulitis might reflect either reactive marrow oedema or true osteomyelitis. More specific signs lend favour to the diagnosis of osteomyelitis: these include focal bone destruction, periosteal reaction and sequestra. The observation of an extramedullary fat-fluid sign is also a specific sign for osteomyelitis, as illustrated in the following case report. This sign is an indication of cortical breach and, thus, in the setting of infection and in the absence of trauma confirms the presence of osteomyelitis. To our knowledge, this additional specific sign of osteomyelitis has not been previously reported on MR.