Acute Glomerulonephritis Flashcards
What is acute acute glomerulonephritis?
This is an infectious allergic disease with predominant localisation of the autoimmune inflammatory process in the vessels of renal glomeruli. Or simply inflammation of glomeruli
Etiology of acute glomerulonephritis
-Infection primarily with B hemolytic streptococcus
Toxic factors like alcohol; drug overdose
Viral origin
Vaccination in patients with predisposing factors
-Tonsillitis
-Exacerbation of chronic tonsillitis
-Inflammation of upper airways
-Scarlet fever in children
Predisposing factor
General cooling that causes vasospasm of arterioles and triggers an allergic reaction in a sensitised organism
Pathogenesis of A.G
Acute G.N is an allergic reaction resulting from sensitisation of an organ to microbial toxins.
Microbial toxins cause changes in the antigenic structure of normal tissue in an organism which acquire properties of foreign antigens and to which ABs begin to be produced.
The ABs are nephrotoxic substances causing autoimmune inflammatory process in renal vessels.
ABs- antistreptolysin,antihyaluronidase,anti streptokinase
Clinical picture of Acute G.N
Patient complains
- edema on face then spreads to subcutaneous tissues and extremities
- headache
- thirst
- dull pain in the lumbar region
- dyspnea
- change in colour of urine
- pale skin due to spasm of skin capillaries and their compression with oedematous fluid
Clinical syndromes in Acute G.N
- Hypertensive
- Diuresis
- Edema
- Urinary
For hypertensive
Pathogenesis connected with pathology of glomerular capillary network and impairment of humoral function of kidney.
Stimulation of juxtaglomerular apparatus causes production of renin which combines with alpha globulin of blood to form angiotensin that possesses a pressor effect.
A stable arterial hypertension leads to a hypertensive syndrome in renal diseases
Renal hypertension is associated with some changes in organs as E.H, hypertrophy and dilation of left ventricle
On examination of eye fundus-reveals changes in retina vessels(retina angiopathy), and in more severe cases retinopathy:Edema
These changes in eye fundus are caused by spasm of vessels and increase in capillary permeability.
Urination
Tea coloured urine present
Causes-proteinuria
-hematuria
-cylinduria
-in nephrotic syndrome leukocyturia
Duration 1month-1year.
Edema
Due to disorders of filtration and reabsoption leading to retention of NaCl and water in tissues,increased capillary permeability,decreased protein concentration in blood
First appears in paraorbital regions and eyelids and then spreads over the face later spreads over the whole body
Diuresis
-may be up to 500-700ml
It’s duration is important in prognosis
Classification of Acute G.N
-By etiology
According to presentation-nephrotic syndrome
- nephritic syndrome 1. nephrotic syndrome - heavy proteinuria (>3.5 g/24hr) - hypoalbunemia - hyperlipidermia - edema 2. nephritic syndrome - a clinical presentation of hypertension - edema - urine sample showing RBCs and a moderate degree of proteinuria
According to nosologic principle- primary and secondary
By course- Acute, subacute,Chronic
By characteristic of inflammation- exudative,productive proliferative, mixed
By morphology-
1.Proliferative- diffused and local
2.Non-proliferative-minimal and membranous
3.Sclerotic/fibroplastic-primary and secondary
By localisation-extra capillary/intracapillary, membranous,mesangium
Lab and instrumental diagnosis of Acute G.N
CBC-anemia, leukocytosis(maybe pancytopenia), increase ESR)
Biochemical-creatinine, urea,electrolytes,lipid profile
-Dipstick and microscopic investigation
To reveal proteinuria,urine sediments (RBCs,casts,in nephrotic type-WBCs)
-Reberg test
(a more detailed functional examination of kidneys including creatinine level,urea, irons like sodium,potassium,calcium,magnesium,chlorine,phosphates,clearance of serum creatinine,daily proteinuria,reabsorbed function)
How to do it- at 8am urination to toilet then from there urine is collected till 8am the next day, with last urination venous blood is taken to evaluate levels of creatinine etc
-Zimnisky test-8 bottles of water,collection of urine every 3hours, the amount and specific gravity is determined.normally daytime diuresis exceeds nighttime, specific gravity varies mostly concentrated in the morning
If ursine function is disordered, specific gravity is reduced in all portions
-Michvaryensky test-detection of RBCs in field of vision, if RBCs more than WBCs its kidney stone
- GFR(norm 90-120ml/min
- Rheumatology and ENT consultation
- Biochemical blood analysis for nephrotic syndrome
- X-ray to exclude other kidney diseases
- US to exclude stone diseases, in nephrotic syndrome edema of pyramids is revealed
- renal biopsy-obligatory,for confirmation and differential diagnosis
- Immunologic-for antistreptolysin O(ASO), antistrotokinase, antihylaruronidase titres may rise.
- ECG signs of hypertension
- Glucose test
Treatment of Acute G.N
-Regime
Bed rest for 1-2weeks
Lying down improves intrarenal hemodynamics(leads to increased renal flow)
Diet
-Full complex of symptoms or nephrotic syndrome
1-2days of strict fasting water intake should match daily diuresis,2-3days rice and potatoes 4-5times a day,salt restriction, day 4-6 protein 40g a day , Carbs 280-320g, fats 80-120g etc
In isolated urinary syndrome- salt restriction
Theurapeutic
Etiologic-antibiotics penicillins e.g amoxicillin for 10-14 days
Diuretics e.g Furosemide 40-80mg a day for edema
- for hypertension - ACEis contraindicated in hyperkalemia.
NSAIDs if symptoms persist for 2 days from beginning of treatment.
-if hypercholesteremia - lipid lowering drugs
Hemodialysis with
Complications of Acute G.N
1.Heart failure
2.Encephalopathy (eclampsia)
Cramps attack mostly in children, develops during edema increase and in HBP, due to increase intracranial pressure, duration of each attack is several seconds till 1-10mins with following sleepiness.Positive babinsky symptoms may be revealed during the attack.
3.Renal failure
Results of physical examination in Acute G.N
Normal GFR= 90-120ml/min
If GFR more than 3 months its chronic kidney disease
-decrease GFR
On physical exam-edema, positive pasternaskiy symptom
