Acute kidney injury in pediatrics: an overview focusing on pathophysiology.

Acute kidney injury (AKI) is defined as an abrupt decline in glomerular filtration rate, with increased serum creatinine and nitrogenous waste products due to several possible etiologies. Incidence in the pediatric population is estimated to be 3.9 per 1,000 hospitalizations, and prevalence among children admitted to intensive care units is 26.9%. Despite being a condition with important incidence and morbimortality, further evidence on pathophysiology and management among the pediatric population is still lacking. This narrative review aimed to summarize and discuss current data on AKI pathophysiology in the pediatric population, considering all the physiological particularities of this age range and common etiologies. Additionally, we reported current diagnostic tools, novel biomarkers, and newly proposed medications that have been studied with the aim of early diagnosis and appropriate treatment of AKI in the future.

Lesions from patients with sporadic cerebral cavernous malformations harbor somatic mutations in the CCM genes: evidence for a common biochemical pathway for CCM pathogenesis.

Cerebral cavernous malformations (CCMs) are vascular lesions affecting the central nervous system. CCM occurs either sporadically or in an inherited, autosomal dominant manner. Constitutional (germline) mutations in any of three genes, KRIT1, CCM2 and PDCD10, can cause the inherited form. Analysis of CCM lesions from inherited cases revealed biallelic somatic mutations, indicating that CCM follows a Knudsonian two-hit mutation mechanism. It is still unknown, however, if the sporadic cases of CCM also follow this genetic mechanism. We extracted DNA from 11 surgically excised lesions from sporadic CCM patients, and sequenced the three CCM genes in each specimen using a next-generation sequencing approach. Four sporadic CCM lesion samples (36%) were found to contain novel somatic mutations. Three of the lesions contained a single somatic mutation, and one lesion contained two biallelic somatic mutations. Herein, we also describe evidence of somatic mosaicism in a patient presenting with over 130 CCM lesions localized to one hemisphere of the brain. Finally, in a lesion regrowth sample, we found that the regrown CCM lesion contained the same somatic mutation as the original lesion. Together, these data bolster the idea that all forms of CCM have a genetic underpinning of the two-hit mutation mechanism in the known CCM genes. Recent studies have found aberrant Rho kinase activation in inherited CCM pathogenesis, and we present evidence that this pathway is activated in sporadic CCM patients. These results suggest that all CCM patients, including those with the more common sporadic form, are potentially amenable to the same therapy.

Prevalence of radiographic appendicular osteoarthritis and associated clinical signs in young dogs.

This study aimed to determine the prevalence of osteoarthritis (OA) and associated clinical signs in young dogs. Owners of dogs aged 8 months-4 years from a single practice, were contacted in random order, to participate in a general health screen. Clinical and orthopedic examinations were performed. Each joint was scored for pain reactions (0-4). Orthogonal radiographs of all joints were made under sedation. Each joint was scored for radiographic OA (rOA) severity on an 11-point scale. Clinical OA (cOA) was defined as an overlap of rOA and joint pain in ≥ 1 joint. Owners completed OA questionnaires. The owners of 123 dogs agreed to participate. Overall, 39.8% (49/123) of dogs had rOA in ≥ 1 joint, and 16.3% (20/123) or 23.6% (29/123) dogs had cOA, depending on the cut-off value of joint pain; moderate (2), or mild (1), respectively. Owners of dogs with cOA observed signs of impairment in approximately 30% of cases. Only 2 dogs with cOA were receiving OA pain management. The most commonly affected joints in descending order of frequency were elbow, hip, tarsus, and stifle. Radiographically visible OA is common in young dogs, and 40-60% of dogs with rOA had cOA. However, OA-pain appears underdiagnosed and undertreated in young dogs.