Autoimmune hepatitis in childhood: The role of genetic and immune factors

Autoimmune hepatitis (AIH) is a rare chronic inflammatory disease of the liver, which affects a group of patients who lost their immunological tolerance to antigens of the liver. It is clinically characterized by hypergammaglobulinemia, elevated liver enzymes, presence of autoantibodies and histological changes. Although being rare in children, it represents a serious cause of chronic hepatic disease that can lead to cirrhosis and hepatic failure. Clinical findings, exclusion of more common liver disorders and the detection of antibodies antinuclear antibodies, smooth muscle antibodies and anti-LKM1 are usually enough for diagnosis on clinical practice. The pathogenic mechanisms that lead to AIH remain obscure, but some research findings suggest the participation of immunologic and genetic factors. It is not yet knew the triggering factor or factors that stimulate inflammatory response. Several mechanisms proposed partially explain the immunologic findings of AIH. The knowledge of immune factors evolved might result in better markers of prognosis and response to treatment. In this review, we aim to evaluate the findings of research about genetic and immune markers and their perspectives of application in clinical practice especially in pediatric population.

Renin angiotensin system in liver diseases: Friend or foe?

In the last three decades,the understanding of the renin angiotensin system(RAS)has been changed by the discoveries of functional local systems,novel biologically active peptides,additional specific receptors,alternative pathways of angiotensin(Ang)?Ⅱ?generation,and new roles for enzymes and precursor components other than those in Ang?Ⅱ?synthesis.In this regard,the discovery that Ang-(1-7)opposes the pressor,proliferative,pro-fibrotic,and pro-inflammatory effects mediated by Ang?Ⅱ?has contributed to the realization that the RAS is composed of two axes.The first axis consists of the angiotensin-converting enzyme(ACE),with Ang?Ⅱ?as the end product,and the angiotensin type 1(AT1)receptor as the main effector mediating the biological actions of Ang?Ⅱ.The second axis results from ACE2-mediated hydrolysis of Ang?Ⅱ,leading to the production of Ang-(1-7),with the Mas receptor as the main effector conveying the vasodilatory,antiproliferative,anti-fibrotic,and anti-inflammatory effects of Ang-(1-7).Experimental and clinical studies have shown that both axes of the RAS may take part in the pathogenesis of liver diseases.In this manuscript,we summarize the current evidence regarding the role of RAS in hepatic cirrhosis and its complications,including hemodynamic changes and hepatorenal syndrome.The therapeutic potential of the modulation of RAS molecules in liver diseases is also discussed.

Psychoeducation in bipolar disorder: A systematic review

BACKGROUND Bipolar disorder(BD)is a severe psychiatric disorder characterized by mood swings.Psychosocial interventions,such as psychoeducation,play an essential role in promoting social rehabilitation and improving pharmacological treatment.AIM To investigate the role of psychoeducation in BD.METHODS A systematic review of original studies regarding psychoeducation interventions in patients with BD and their relatives was developed.A systematic literature search was performed using the Medline,Scopus,and Lilacs databases.No review articles or qualitative studies were included in the analysis.There were no date restriction criteria,and studies published up to April 2021 were included.RESULTS A total of forty-seven studies were selected for this review.Thirty-eight studies included patients,and nine included family members.Psychoeducation of patients and family members was associated with a lower number of new mood episodes and a reduction in number and length of stay of hospitalizations.Psychoeducational interventions with patients are associated with improved adherence to drug treatment.The strategies studied in patients and family members do not interfere with the severity of symptoms of mania or depression or with the patient's quality of life or functionality.Psychoeducational interventions with family members do not alter patients'adherence to pharmacotherapy.CONCLUSION Psychoeducation as an adjunct strategy to pharmacotherapy in the treatment of BD leads to a reduction in the frequency of new mood episodes,length of hospital stay and adherence to drug therapy.

Inherited Fanconi syndrome

Background Fanconi-Debré-de Toni syndrome(also known as Fanconi renotubular syndrome,or FRST)profoundly increased the understanding of the functions of the proximal convoluted tubule(PCT)and provided important insights into the pathophysiology of several kidney diseases and drug toxicities.Data sources We searched Pubmed and Scopus databases to find relevant articles about FRST.This review article focuses on the physiology of the PCT,as well as on the physiopathology of FRST in children,its diagnosis,and treatment.Results FRST encompasses a wide variety of inherited and acquired PCT alterations that lead to impairment of PCT reab-sorption.In children,FRST often presents as a secondary feature of systemic disorders that impair energy supply,such as Lowe's syndrome,Dent's disease,cystinosis,hereditary fructose intolerance,galactosemia,tyrosinemia,Alport syndrome,and Wilson's disease.Although rare,congenital causes of FRST greatly impact the morbidity and mortality of patients and impose diagnostic challenges.Furthermore,its treatment is diverse and considers the ability of the clinician to identify the correct etiology of the disease.Conclusion The early diagnosis and treatment of pediatric patients with FRST improve the prognosis and the quality of life.

Bartter's syndrome:clinical findings,genetic causes and therapeutic approach

Backgound Bartter's syndrome(BS)is a rare group of salt losing tubulopathies due to the impairment of transport mecha-nisms at the thick ascending limb of the Henle's loop.Data sources Literature reviews and original research articles were collected from database,including PubMed and Scopus.Results According to the time of onset and symptoms,BS can be classified into antenatal and classic BS.Molecular studies have identified different subtypes of BS.BS types Ⅰ,Ⅱ and Ⅲ are caused by mutations on genes encoding the luminal Na^(+)-K^(+)-2Cl^(-) co-transporter,the luminal K+ channel ROMK,and the basolateral chloride channel ClC-Kb(CLCNKB),respectively.Loss-of-function mutations of Barttin CLCNK type accessory beta subunit cause BS type Ⅳa.Simultaneous mutations of CLCNKB and CLCNKA cause BS type Ⅳb.BS type Ⅴ consists in a novel transient form characterized by antenatal presentation due to mutations in the MAGE family member D2.Severe gain-of-function mutations of the extracellular calcium sensing receptor gene can result in an autosomal dominant condition of BS.Main clinical and biochemical alterations in BS include polyuria,dehydration,hypokalemia,hypochloremic metabolic alka-losis,hyperreninemia,high levels of prostaglandins,normal or low blood pressure,hypercalciuria and failure to thrive.Treatment focuses mainly at correcting dehydration and electrolyte disturbances and in measures to reduce polyuria,including the use of nonsteroidal anti-inflammatory medications to control excessive renal prostaglandin E2 production.Conclusions Early diagnosis and treatment of BS may prevent long-term consequences such as growth failure,nephrocal-cinosis and end-stage renal disease.

Distal renal tubular acidosis:genetic causes and management

Background Distal renal tubular acidosis(dRTA)is a kidney tubulopathy that causes a state of normal anion gap metabolic acidosis due to impairment of urine acidification.This review aims to summarize the etiology,pathophysiology,clinical findings,diagnosis and therapeutic approach of dRTA,with emphasis on genetic causes of dRTA.Data sources Literature reviews and original research articles from databases,including PubMed and Google Scholar.Manual searching was performed to identify additional studies about dRTA.Results dRTA is characterized as the dysfunction of the distal urinary acidification,leading to metabolic acidosis.In pediatric patients,the most frequent etiology of dRTA is the genetic alteration of genes responsible for the codification of distal tubule channels,whereas,in adult patients,dRTA is more commonly secondary to autoimmune diseases,use of medications and uropathies.Patients with dRTA exhibit failure to thrive and important laboratory alterations,which are used to define the diagnosis.The oral alkali and potassium supplementation can correct the biochemical defects,improve clinical manifestations and avoid nephrolithiasis and nephrocalcinosis.Conclusions dRTA is a multifactorial disease leading to several clinical manifestations.Clinical and laboratory alterations can be corrected by alkali replacement therapy.