Postinfective Glomerulonephritis ( PIGN ) in Children Attending a Tertiary Care Centre in Nepal

Introduction: Post infectious glomerulonephritis (PIGN) is one of the common paediatric kidney disease in developing countries. This study was undertaken to describe the common clinical features, biochemical findings and complications in children with PIGN. Materials and Methods: This was a retrospective descriptive study in which 30 patients admitted with a diagnosis of PIGN at Tribhuvan University Teaching Hospital (TUTH) in a six month period (July 2014 to Dec 2014) were included. Hospital medical records were reviewed for the data collection. Results: Out of 30 patients, 24 (80%) were between 5 to 15 years of age (mean age of 11.5±3.3) with male to female ratio of 2.3:1. Pedal oedema and hypertension were the clinical features seen in 29 (97%) and 28 (93%) patients respectively. Hypocomplementemia was found in 29 (97%) patients. Recent past history of sore throat seen in 10 (33%) patients and skin lesions in 12 (40%). The complications noted were congestive cardiac failure in 5 (17%) patients, rapidly proliferative glomerulonephritis in 3 (10%) and encephalopathy in 1(3%). Conclusion: The most important clinical and biochemical profile observed in nepalese children with PIGN are the hypertension, pedal edema and hypocomplementemia.


Introduction
A GN (Acute glomerulonephri s) is recognized by clinical features of haematuria, fl uid overload (edema and hypertension), and some evidence of renal insuffi ciency (eleva on of blood urea nitrogen and crea nine) 1 .Post infec ve glomerulonephri s (PIGN) is the commonest form of AGN in developing countries 2 .Children from 4-14 years of age are more commonly aff ected by PIGN and is twice more frequent in males than females 3 .Although nephritogenic beta hemoly c streptococci cons tute the commonest cause of PIGN, several other bacteria and viruses have also been implicated 4 .In this study therefore, a terminology PIGN has been used instead of Post streptococcal glomerulonephri s (PSGN).In the absence of highly sensi ve diagnos c modality in resource poor countries, the defi ni ve infec ve e ology cannot be established in many pa ents presen ng with AGN.Since there are no defi ni ve diagnos c criteria for PIGN, the trea ng clinician usually makes a fi nal diagnosis of PIGN a er reviewing all clinical features and biochemical parameter and excluding other causes of glomerulonephri s whenever necessary.
This study aims to describe the common clinical features, biochemical fi ndings and complica ons in children with PIGN admi ed to our hospital.

Materials and Methods
This is a retrospec ve descrip ve study in which 30 pa ents with a fi nal diagnosis of PIGN at Tribhuvan University Teaching Hospital (TUTH) in six month's period (July 2014 to Dec 2014).Final diagnosis was made on the basis of clinical features (such as edema, hematuria, hypertension, oliguria), laboratory analyses (such as deranged renal func on, ASO tre, complement level, ANA) with or without recent past history of skin and/or throat infec on.Hospital medical records were reviewed for demographic profi les, clinical features, complica ons, laboratory data and treatment.The data was analysed in descrip ve method and results obtained are shown in the form of frequencies along with the percentage values.

Results
Out of a total of 30 pa ents, 24 (80%) were between 5 to 15 years of age (mean age of 11.5±3.3)with male to female ra o of 2.3:1.Twelve (40%) pa ents were referred from other hospitals.There were maximum number of pa ents in the month of November (9) and December (12).Dura on of stay in hospital ranged from 2 to 15 days (mean dura on of 7.86±3.84).
The common clinical features were swelling of face and/or leg (100%), hypertension (93.33%), decreased urine output (56.67%) and red coloured urine (46.67%).Eleven (36.67%) pa ents had other features like fever, abdominal pain, bleeding from nose, cough, diffi culty in breathing and seizure.Recent history of sore throat and skin lesion were seen in 33% pa ents and 40% respec vely.(Table 1) Among 30 pa ents, elevated ASO tre was observed in only 60% of pa ents.Though there was a history of gross hematuria in 46.67%, microscopic hematuria was observed in 67% of pa ents.C3 was sent in all pa ents and was found to be decreased in 97%.Renal func on derangement was seen in only 50%.Serum electrolytes (Na, K ) were found to be normal in all pa ents.ANA was done in 9 pa ents (30%) but was nega ve in all.(Table 2) Ultrasound of the kidney was done in fi ve pa ents (1 had associated urinary tract infec on, 3 had associated pallor, 1 had short stature) and found to be normal.Three pa ents with clinical suspicion of RPGN (rising crea nine with decreasing urine output) underwent kidney biopsy which showed crescen c glomerulonephri s in all.
Out of 30 pa ents, nine (30%) had complica ons.The complica ons noted were conges ve cardiac failure in 17%, rapidly prolifera ve glomerulonephri s (RPGN) in 10% and encephalopathy in 3% of pa ents.Four (13.33%) had associated problems like infected eczema (3.3%), urinary tract infec on (3.3%) and nephro c range proteinuria (6.7%).(Table 3) Diure c and nifedipine were the an hypertensives used in 97% and 77% of pa ents respec vely.Seventy seven percent of the total pa ents received both the drugs to control hypertension.Hypertension disappeared within 3 to 12 days with mean dura on of 6.6 ± 2.7 days.Dialysis required in one pa ent ( 3% ).Three pa ents of RPGN received methylprednisolone.

Discussion
This study was carried out in six month period from July to December among 30 pa ents admi ed at TUTH with fi nal diagnosis of PIGN.To the best of our knowledge, this is the fi rst published study on PIGN among Nepalese popula on.
The prevalence is higher among school going age of 5 to 15 years.Similar observa on were reported by some previous studies 3,5,6 .Regarding sex, we observed more cases of PIGN in male individual.This may be due to the fact that male children are ac ve and liable to get infec on more than female.In our study, pyoderma associated nephri s with male individual are predominant which are comparable to other studies 5,6,7,8 .
Our study, in accordance with other four studies, showed edema, hematuria, hypertension and low complement level in signifi cant number of pa ents. 6,9,10,11The depression of C3 has been found to be the most reliable indicator of PIGN.All of our pa ents, except one, had signifi cantly depressed C3 level.Similar observa on was also seen in a study by Fabiola D Cruz et al 12 .However elevated ASO tre and deranged renal func on was seen in only 60 and 50% respec vely.There might be several reasons of not having elevated ASO tre in majority of our pa ents.Firstly, antecedent infec on may not be streptococcal in origin in large number of our pa ents.Secondly, most of our pa ents were pyoderma related where we rarely get elevated ASO tre in the blood.Thirdly, an DNAse B (ADN-B) test, which usually gets elevated in pyoderma associated nephri s, could not be done in our se ng because of unavailability of the men oned test.In a report by Chug K S et al, the u lity of ASO ters in pa ents with acute glomerulonephri s following streptococcal pyoderma is lower, with elevated concentra ons in only 57%; however ADN-B is more consistently elevated (90%) making it the serologic test of choice in this se ng 13 .Some of the previous studies had even made their own criteria while including cases of PIGN.In a study by Khoybar MA et al, poststreptococcal glomerulonephri s was defi ned as recent onset of haematuria or history of haematuria plus either of the followings or all: oedema, renal insuffi ciency, hypertension, heart failure, hypertensive encephalopathy, evidence of recent streptococcal infec on (posi ve throat/Swab culture, history of skin infec on or pharyngi s or elevated ASO.tre) 5 .In a study by S Rajajee, criteria for APSGN (acute poststreptococcal glomerulonephri s) made were acute onset of edema, oliguria, hematuria, proteinuria, no history of antecedent renal disease and recent history of skin and/or throat infec on 14 .However, with the variability of clinical features and lab parameter, we had not made any criteria and fi nal diagnosis of PIGN was made by the trea ng paediatrician a er reviewing all clinical features and laboratory parameters.We observed that blood pressure was controlled within 3 to 12 days with an average of 6.6 days which was not diff erent from other studies 5,15 .
Besides, the typical features, PIGN occasionally manifests with one or more of its complica ons, while edema and gross hematuria may be absent.In series of studies, the common complica ons seen were acute pulmonary edema, hypertensive encephalopathy, acute renal failure and nephro c syndrome 5,14,16 .The most common complica ons noted in our study were conges ve cardiac failure (17%), RPGN (10%) and encephalopathy (3%).In a study by Fabiola D, Cruz et al, hypertensive encephalopathy and conges ve cardiac failure were found in 11.3% and 36.3%respec vely 12 .In our study, only two pa ents (6.67%) had nephro c range proteinuria.However, in a study by Chug KS et al, 14% of PSGN pa ent was found to have nephro c range proteinuria at the onset 13 .Three of our pa ents (10%) had clinical presenta on of RPGN, which revealed crescen c glomerulonephri s on renal biopsy.Study by Marques et al showed RPGN in 1.2% in age group beyond 14 years 11 .Out of 30 cases studied, there was no deaths in the present study.The mortality rate seemed to vary from <1% to 13% in other previous studies 7,14 .

Conclusion
The most important clinical and biochemical profi le observed in Nepalese pa ents a ending this ter ary care centre with a diagnosis of PIGN are hypertension, pedal oedema and hypocomplementemia.