"" Haemolytic Uraemic Syndrome (HUS): Clinical Medicine Versus Clinical Anatomy

Review Article

Austin J Anat. 2017; 4(1): 1064.

Haemolytic Uraemic Syndrome (HUS): Clinical Medicine Versus Clinical Anatomy

Muhammad SN¹*, Abdel Meguid E²* and Robert Novo’s³

¹Specialist Biomedical Scientist, Co-Founder and Chief in Research, Renal Patient Support Group (RPSG), UK

²Centre for Biomedical Sciences Education, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University Belfast, UK

³Hospital Practitioner, Paediatric Nephrologic Unit, University Hospital, Lille, France

*Corresponding author: Muhammad SN, Specialist Biomedical Scientist, Co-Founder and Chief in Research, Renal Patient Support Group (RPSG), England, UK

Received: January 16, 2017; Accepted: February 13, 2017; Published: February 16, 2017

Abstract

Haemolytic Uraemic Syndrome (HUS) is an acquired disorder affecting mainly infants and children. The triad of this clinical syndrome is defined by: 1) Thrombotic or Microangiopathic Haemolytic Anaemia with schistocytes 2) Thrombocytopenia and 3) Acute Renal Failure (ARF) which can develop into Chronic Kidney Disease (CKD). The aim of this article is to provide an editorial/ commentary on the Clinical Medicine versus Clinical Anatomy of HUS.

HUS is the most common cause of Acute Renal Failure (ARF) in children with an equal sex incidence [1]. The annual incidence of VTEC infection varies geographically; it can range from 1 to 30 cases per 100,000 in industrialized countries. It is a rare syndrome post-puberty but it is also closely related to Thrombotic Thrombocytopenia (TTP) which is common in adults. The annual incidence of the Verocytotoxin-producing Esherichia Coli (VTEC) infection varies geographically from year to year, ranging from 1-30 cases per 100,000 in industrialized countries and is associated with HUS. HUS occurs in sporadic cases epidemics; between 1st January [2] and 31st December [2] in England, a total of 3717 cases were reported with evidence of Shiga Toxin-Producing E. Coli (STEC) infection; sometimes following outbreaks. In Hamburg [3], there was an outbreak with more than 900 cases. The disease has seasonal variation, being more common in the warmer months in children.

Renal histopathology is characterized by abnormal morphology applicable to afferent arterioles and glomeruli. The glomeruli show evidence of global sclerosis and glomerular thrombotic microangiopathy endothelial cell swelling; capillary wall thickening and glomerular basement membranes also evident. Interstitial fibro edematous change and tubular atrophy are marked. Arterial, arteriolar and capillary lumina are narrow with obstruction and intimal thickening. The nature of vascular involvement in the kidneys supports the hypothesis that HUS is mediated by systemic toxemia and endothelial cells are the primary target cells owing to action of Verocytotoxin. Histopathological findings provide clues not only to the diagnosis but also in the support of prognosis. Diffuse tubular interstitial change and global sclerosis indicate the degree of blood flow obstruction and prognosis. Renal blood flow obstruction caused by diffused arterial and arteriolar luminal stenosis may lead to irreversible changes in renal pathology

Keywords: Haemolytic Uraemic Syndrome (HUS); Clinical medicine; Clinical anatomy; Chronic kidney disease; Acute renal failure; Haematology

Introduction

Haemolytic Uraemic Syndrome (HUS) occurs due to Shigalike toxin activity via aberrant complement activation. HUS is typically classified into two primary types: 1) HUS due to infections, often associated with diarrohea (D+HUS, Shiga toxin-producing Escherichia Coli-HUS), with the rare exception of HUS due to a severe disseminated infection caused by Streptococcus; 2) HUS related to complement, such HUS is also known as “atypical HUS” and is not diarrohea associated (D-HUS, aHUS) [4]. Clinical features include proteinuria, renal impairment and history of E. coli diarrohea (hallmark of typical HUS). Encephalopathy is rare but can cause death. HUS is seen increasingly following outbreaks of infection with Verotoxin (VT)-producing organisms. It represents a growing public health problem and data suggest that more awareness of specific micro-organisms causing diarrhoea, (and those thus leading to HUS and/ or HUS related symptoms) may become more important in future health consultations [3].

E.coli 0157:H7 is the most commonly notified VT-producing organism in the UK and France. Clinical manifestations may vary from an asymptomatic infection to bloody diarrhoea, haemorrhagic colitis and HUS. Verotoxin Enterococcal (VTEC)-associated HUS was seen in up to 20% of patients in recent outbreaks, mainly affecting children [5]. Table 1 summarizes the defining classification of HUS and (Table 2) summarizes features of HUS, respectively.