Atypical hemolytic uremic syndrome (aHUS) is a rare disorder characterized by dysregulation of the alternate pathway. The diagnosis of aHUS is one of exclusion, which complicates its early detection and corresponding intervention to mitigate its high rate of mortality and associated morbidity. Heterozygous mutations in complement regulatory proteins linked to aHUS are not always phenotypically active, and may require a particular trigger for the disease to manifest. This list of triggers continues to expand as more data is aggregated, particularly centered around COVID-19 and pediatric vaccinations. Novel genetic mutations continue to be identified though advancements in technology as well as greater access to cohorts of interest, as in diacylglycerol kinase epsilon (DGKE). DGKE mutations associated with aHUS are the first non-complement regulatory proteins associated with the disease, drastically changing the established framework. Additional markers that are less understood, but continue to be acknowledged, include the unique autoantibodies to complement factor H and complement factor I which are pathogenic drivers in aHUS. Interventional therapeutics have undergone the most advancements, as pharmacokinetic and pharmacodynamic properties are modified as needed in addition to their as biosimilar counterparts. As data continues to be gathered in this field, future advancements will optimally decrease the mortality and morbidity of this disease in children.

Background: Hypertension is one of the most prevalent diseases in the United States, affecting an estimated 3.5% of children and adolescents. It can be adversely affect most organ systems but is particularly detrimental to the heart and vascular systems. The repercussions can be gauged through well-established measures of cardiovascular function including left ventricular mass index (LVMI), left ventricular hypertrophy (LVH), carotid intima media thickness (cIMT), and aortic stiffness. Cardiovascular function is also affected by underlying etiologies of hypertension including chronic kidney disease, polycystic kidney disease, coarctation of the aorta, adrenal disorders, renal artery stenosis, obstructive sleep apnea, as well as various drugs and medications (decongestants, stimulants, Non-steroidal Anti-inflammatory Drugs (NSAIDs), and steroids). Methods: An exhaustive literature search was conducted for clinical data regarding pediatric hypertension. Sixty-seven articles were incorporated with data on 189,477 subjects total. The data was then extracted and categorized as relating to hypertension incidence, LVMI, LVH, cIMT, and/or aortic stiffness. Results: The prevalence of pediatric ( 18 years) hypertension extracted from 47 studies from 1994 to 2018 averaged 4%. The LVMI assessed over 7 studies (n = 661) averaged 39.3 g/ in the hypertensive cohort and 30.1 g/ in the control cohort. The cIMT assessed over 7 studies (n = 580) averaged 0.55 mm in the hypertensive cohort and 0.49 mm in the control cohort. Ambulatory arterial stiffness parameters assessed over 5 studies (n = 573) in the normotensive cohort averaged 99.73 mmHg, 69.81 mmHg, 76.85 mmHg, and 46.90 mmHg, for SBP, DBP, MAP, and PP respectively. Ambulatory arterial stiffness parameters assessed over 5 studies (n = 573) in the hypertensive cohort averaged 129.56 mmHg, 73.69 mmHg, 95.08 mmHg, and 56.80 mmHg, for SBP, DBP, MAP, and PP respectively. Conclusions: The significance of pediatric hypertension is emphasized by evidence of early cardiovascular disease as demonstrated by non-invasive measures including cIMT and arterial stiffness parameters, and target organ damage and including LVH and LVMI factors. Thus, early diagnosis and treatment of high blood pressure is paramount for improving long term cardiovascular health and preventing long term morbidity and mortality.