Nephrology & Renal Flashcards
what is a UTI?
infection anywhere along the urinary tract - urethra, bladder, kidney
what is meant by cystitis?
inflammation of the bladder, and can be the result of a bladder infection.
what must be excluded when a child has a fever?
UTI - fever may be the only symptom
how does a UTI present in babies?
- very non specific symptoms:
- Fever
- Lethargy
- Irritability
- Vomiting
- Poor feeding
- Urinary frequency
what are some signs and symptoms for older infants and children?
- Fever
- Abdominal pain- suprapubic
- vomiting
- Dysuria
- Urinary frequency
- Incontinence
what is acute pyelonephritis?
infection affects the tissue of the kidney. It can lead to scarring in the tissue and consequently a reduction in kidney function.
when can a diagnosis of pyelonephritis be made?
Diagnosis made if either there is:
- Temp>38
- Loin pain or tenderness
what is the ideal urine sample?
clean catch sample - avoiding contamination
parent may have to sit with infant without nappy on waiting to catch urine in pot
what do nitrites indicate on a dip stick?
suggests bacterial infection - presence of bacteria in urine - gram negative bacteria break down nitrates (normal waste product in urine) into nitrites
better indication of infection than leukocytes
what do leukocytes on dip stick indicate?
normally small number of WBC in urine but significant rise can be bc infection or other cause of inflammation
urine dipstick tests for leukocyte esterase
when are patients treated for uti regarding nitrites and leukocytes on dip stick?
if both nitrites and leukocytes - treat as UTI
if only nitrites - treat as UTI
if only leukocytes - do not treat unless clinical evidence they have UTI
when should urine be sent to the microbiology lab?
if nitrites or leukocytes are present
send for culture and sensitivity testing
how is UTI managed?
all children under 3 months with fever - IV abx - ceftriaxone and full septic screen (cultures, bloods, lactate) also consoder lumbar puncture
oral abx in children >3 months if otherwise well
sepsis or pyelonephritis - IV abx
name 4 abx that can be used in children with uti?
- Trimethoprim
- Nitrofurantoin
- Cefalexin
- Amoxicillin
what are the guidelines of USS for children with UTI?
- All children <6 months with their first UTI should have an abdominal ultrasound within 6 weeks, or during the illness if there are recurrent UTIs or atypical bacteria
- Children with recurrent UTIs should have an abdominal ultrasound within 6 weeks
- Children with atypical UTIs should have an abdominal ultrasound during the illness
what is a DMSA scan?
dimercaptosuccinic acid scan
used 4-6 months after illness to assess for damage from recurrent or atypical UTIs
injecting radioactive material and using a gamma camera to assess how well the material is taken up by the kidneys
where there are patches that have not taken up the material - indicated scarring from previous infection
what is vesico-ureteric reflux
where urine has a tendency to flow from the bladder back into the ureters. This predisposes patients to developing upper urinary tract infections and subsequent renal scarring.
how is VUR diagnosed?
micturating cystourethrogram (MCUG)
how is VUR managed?
- Avoid constipation
- Avoid an excessively full bladder
- Prophylactic antibiotics
- Surgical input from paediatric urology
what is a Micturating cystourethrogram (MCUG)?
Micturating cystourethrogram (MCUG) should be used to investigate atypical or recurrent UTIs in children under 6 months. It is also used where there is a family history of vesico-ureteric reflux, dilatation of the ureter on ultrasound or poor urinary flow.
It involves catheterising the child, injecting contrast into the bladder and taking a series of xray films to determine whether the contrast is refluxing into the ureters. Children are usually given prophylactic antibiotics for 3 days around the time of the investigation.
what is vulvovaginitis?
inflammation and irritation of the vulva and vagina. It is a common condition often affecting girls between the ages of 3 and 10 years.
what causes and exacerbates vulvovaginitis?
Caused by sensitive thin skin and mucosa around the vulva and vagina in young girls. More prone to colonisation and infection with bacteria spread from faeces. Can be exacerbated by:
- Wet nappies
- Use of chemicals or soaps cleaning the area
- Tight clothing that traps moisture or sweat in the area
- Poor toilet hygiene
- Constipation
- Threadworms
- Pressure on the area, for example horse riding
- Heavily chlorinated pools
how does vulvovaginitis present?
- Soreness
- Itching
- Erythema around labia
- Vaginal discharge
- Dysuria
- Constipation
Urine dip may show leukocytes but no nitrites. Often misdiagnosed UTI
how is vulvovaginitis managed?
May already have been treated for UTI and thrush, usually with little improvement in symptoms. (Unusual to develop thrush before puberty)
No medical just conservative:
- Avoid washing with soap and chemicals
- Avoid perfumed or antiseptic products
- Good toilet hygiene, wipe from front to back
- Keeping the area dry
- Emollients, such as sudacrem can sooth the area
- Loose cotton clothing
- Treating constipation and worms where applicable
- Avoiding activities that exacerbate the problem
Severe cases an experienced paediatrician may be recommend oestrogen cream to improve symptoms.
what is nephrotic syndrome?
occurs when the basement membrane in the glomerulus becomes highly permeable to protein, allowing proteins to leak from the blood into the urine.
what is the most common age group to develop nephrotic syndrome
between 2 and 5 years
how does nephrotic syndrome present?
frothy urine
generalised oedema
pallor
what is the triad of nephrotic syndrome?
- Low serum albumin
- High urine protein content (>3+ protein on urine dipstick)
- Oedema
Aside from low serum albumin, high urine protein content (>3+ protein on urine dipstick) and oedema what are 3 further features of nephrotic syndrome?
- Deranged lipid profile, with high levels of cholesterol, triglycerides and low density lipoproteins
- High blood pressure
- Hyper-coagulability, with an increased tendency to form blood clots
what is the most common cause of nephrotic syndrome?
minimal change disease
Name 2 causes where it is secondary to intrinsic kidney disease?
- Focal segmental glomerulosclerosis
- Membranoproliferative glomerulonephritis
what are 3 systemic illnesses which nephrotic syndrome can be secondary to?
- Henoch schonlein purpura (HSP)
- Diabetes
- Infection, such as HIV, hepatitis and malaria
What is minimal change disease?
most common cause of nephrotic syndrome in children. It can occur in otherwise healthy children, without any clear risk factors or reason for developing the condition. It is not clear why it occurs in most cases.
A renal biopsy and standard microscopy in minimal change disease is usually not able to detect any abnormality. Urinalysis (analysis of the urine) will show small molecular weight proteins and hyaline casts.
how is minimal change disease managed?
corticosteroids (i.e. prednisolone). The prognosis is good and most children make a full recovery, however it may reoccur.
how is nephrotic syndrome managed?
- High dose steroids (i.e. prednisolone)
- Low salt diet
- Diuretics may be used to treat oedema
- Albumin infusions may be required in severe hypoalbuminaemia
- Antibiotic prophylaxis may be given in severe cases
high dose steroids are used to treat nephrotic syndrome - describe the responses and how steroid resistant children are managed?
- 80% of children will respond to steroids, and are referred to as steroid sensitive
- 80% of steroid sensitive patients will relapse at some point and need further steroids
- Patients that struggle to wean steroids due to relapses are referred to as steroid dependant
- Patients that do not respond to steroids are referred to as steroid resistant
In steroid resistant children, ACE inhibitors and immunosuppressants such as cyclosporine, tacrolimus or rituximab may be used.
what are some complications of nephrotic syndrome?
- Hypovolaemia occurs as fluid leaks from the intravascular space into the interstitial space causing oedema and low blood pressure.
- Thrombosis can occur because proteins that normally prevent blood clotting are lost in the kidneys, and because the liver responds to the low albumin by producing pro-thrombotic proteins.
- Infection occurs as the kidneys leak immunoglobulins, weakening the capacity of the immune system to respond. This is exacerbated by treatment with medications that suppress the immune system, such as steroids.
- Acute or chronic renal failure
- Relapse
what is nephritis?
Nephritis refers to inflammation within the nephrons of the kidneys
what does nephritic cause?
- Reduction in GFR
- Haematuria
- Proteinuria (less than nephrotic)
what are the 2 most common causes of nephritis in children?
Post-streptococcal glomerulonephritis
IgA nephropathy (Berger’s disease)
what is post-streptococcal glomerulonephritis?
Occurs 1-3 weeks after a B-haemolytic streptococcus infection, such as tonsillitis caused by strep pyogenes
Immune complexed made up of streptococcal antigens, antibodies and complement proteins get stuck in the glomeruli of the kidney and cause inflammation. Inflam= acute deterioration in renal function causing AKI.
when should a diagnosis Post-Streptococcal Glomerulonephritis be suspected?
when there is evidence of tonsillitis caused by strep. This could be a hx tonsillitis, positive throat swab and anti-streptolysin antibody titres found on a blood test.
how is Post-Streptococcal Glomerulonephritis managed?
supportive and around 80% of patients will make a full recovery.
some patients can develop a progressive worsening of their renal function.
They may need treatment with antihypertensive medications and diuretics if they develop complications such as hypertension and oedema.
what is IgA nephroapthy?
aka Bergers disease
related to Henoch-Schonlein Purpura, which is an IgA vasculitis.
IgA deposits in the nephrons of the kidney causes inflammation (nephritis).
When a renal biopsy is taken the histology will show “IgA deposits and glomerular mesangial proliferation”.
It usually presents in teenagers or young adults.
Management involves supportive treatment of the renal failure and immunosuppressant medications such as steroids and cyclophosphamide to slow the progression of the disease.
what is a posterior urethral valve?
A posterior urethral valve is where there is tissue at the proximal end of the urethra (closest to the bladder) that causes obstruction of urine output. It occurs in newborn boys. The obstruction to the outflow of urine creates a back pressure into the bladder, ureters and up to the kidneys, causing hydronephrosis. A restriction in the outflow of urine prevents the bladder from fully emptying, leading to a reservoir of urine that increases the risk of urinary tract infections.
what is hypospadias?
condition affecting males, where the urethral meatus (the opening of the urethra) is abnormally displaced to the ventral side (underside) of the penis, towards the scrotum. This might be further towards the bottom of the glans (in 90% of cases), halfway down the shaft or even at the base of the shaft.
what is hypospadias?
condition affecting males, where the urethral meatus (the opening of the urethra) is abnormally displaced to the ventral side (underside) of the penis, towards the scrotum. This might be further towards the bottom of the glans (in 90% of cases), halfway down the shaft or even at the base of the shaft.
what is Epispadias?
Epispadias is where the meatus is displaced to the dorsal side (top side) of the penis
what is a hydrocele?
collection of fluid in tunica vaginalis that surrounds the teste.
tunica vaginalis is a sealed pouch of membrane that surrounds the testes.
Originally the tunica vaginalis is part of the peritoneal membrane, but during development of the fetus it becomes separated from the peritoneal membrane and remains in the scrotum, partially covering each testicle.
what investigations are done for testicular torsion?
clincal dx - surgical exploration within 4-6 hours as surgical emergency
uss - whirlpool sign - spiral appearance to the spermatic cord and blood vessels
