Nephrology Flashcards
A 1-month-old baby attends accident and emergency with a 2-day history of fever to 38.8°C measured at the GP surgery. He has been vomiting, with no diarrhoea, rash, cough or coryza. A clean catch urine has leukocytes +++ and ketones, no nitrites, blood or protein. An urgent microscopy shows >200 cells/μL white cells. What is the most appropriate course of action?
A. Discharge home with 3 days of trimethoprim
B. Admit for a course of IV antibiotics to cover a urinary tract infection (UTI)
C. Admit for a lumbar puncture, blood cultures and chest x-ray, IV antibiotics
D. Organize an urgent DMSA scan
E. Discharge home with reassurance and advice to return if fever persists
C. Admit for a lumbar puncture, blood cultures and chest x-ray, IV antibiotics
1 CThis child has a non-specific presentation. The differential diagnosis of vomiting in children is broad including infection, surgical, reflux and raised intracranial pressure. This child is febrile which increases the suspicion of infection; however, in children under 3 months a febrile presentation requires a thorough search for the cause. Therefore this child needs a septic screen which includes, blood culture, urine cultures, cerebrospinal fluid cultures, chest x-ray and C-reactive protein – (C) and not (E). Although the urine has leukocytes, these are not sensitive on their own or in infants. This child should not be discharged until a focus has been found for the infection (A). If the urine culture grows >105 colony-forming units per millilitre of a single organism, the diagnosis of a UTI can be made and then (B) would be correct. These children will require imaging of the renal tract with ultrasound, DMSA and micturating cystourethrogram depending on age (see NICE guidelines on UTI in children), though a DMSA scan is done at least 6 weeks after the infection (D) as it can be misleading in the acute situation of infection.
A 5-year-old boy presents to his GP with a 3-day history of puffy eyes. He has been unwell with a coryzal illness for the last week. His mother states he has had no new medications and no hayfever, allergies or asthma. On further examination he has generalized oedema and scrotal oedema. He is tachycardiac and has cool peripheries, no skin rashes or erythema. What is the most likely diagnosis?
A. Periorbital cellulitis
B. Allergic reaction
C. Nephrotic syndrome
D. Nephrotic syndrome with hypovolaemia
E. C1 esterase deficiency
D. Nephrotic syndrome with hypovolaemia
2 DNephrotic syndrome (triad of proteinuria, hypoalbuminaemia and generalized oedema) presents with puffy eyes, which could also be a feature of any of the above diagnoses. However, the examination findings of generalized oedema make periorbital cellulitis (A) (in the absence of a fever) and allergic reaction (in the absence of skin rash, wheals, flares) (B) unlikely. The diagnosis of nephrotic syndrome (C) precipitated by an intercurrent infection in this case is correct, but with tachycardia and cool peripheries this suggests this child additionally has hypovolaemia, due to increased interstitial fluid collection due to reduced oncotic pressure (D). Rarely, C1 esterase deficiency (E) can present with generalized oedema following an intercurrent illness.
A 12-year-old girl presents to her GP with a UTI. She has no past medical history of note and is not taking any medication. On testing her routine observations, her blood pressure was 140/90 mmHg with a manual sphygmomanometer. You are concerned this may be high for her age. She has no headaches, visual disturbance, vomiting, chest pain, dyspnoea or neurological signs. What is your next course of action?
A. Repeat the blood pressure on three different occasions
B. Discuss the blood pressure reading with a paediatric nephrologist
C. Commence sodium nitroprusside
D. Repeat the blood pressure measurements with an automated machine E. Discharge home with reassurance
A. Repeat the blood pressure on three different occasions
3 ABlood pressure measurements in children need the same considerations as for adult patients. There may be external factors influencing the reading such as pain, anxiety, incorrect cuff size and poor technique. Manual measurements are preferable to automated ones (D). The blood pressure should be repeated on at least three occasions (A) and if still high investigations and management should be initiated with guidance from paediatric nephrologists (B). Sodium nitroprusside (C) is the treatment of choice for malignant hypertension, which is not consistent with the history. Causes of hypertension in children include: essential hypertension, renal (renal artery stenosis, chronic kidney disease, Wilms’ tumour), cardiac (coarctation of the aorta), endocrine (Cushing’s syndrome, phaeochromocytoma, neuroblastoma) and metabolic (hyperaldosteronism, congenital adrenal hyperplasia). Therefore, simple discharge home is not acceptable without considered exploration (E).
A 6-year-old girl presents to hospital with a large right-sided abdominal mass. It does not cross the midline. On further questioning she has had macroscopic haematuria and weight loss of 4 kg over the last 4 months. She has reduced appetite and lethargy. Her blood pressure is 125/73 mmHg, heart rate 120 bpm. Which of the following is not a complication of this malignancy?
A. Malnutrition
B. Hypertension
C. Renal impairment
D. Urinary catecholamines
E. Metastatic spread
D. Urinary catecholamines
4 D Wilms’ tumour can result in hypertension (B) and renal impairment
(C), dependent on the functioning of the contralateral kidney. General complications of malignant disease include metastases (E) and malnutrition (A) due to poor appetite, vomiting and increased metabolic demands. Sympathetic nervous system stimulation does not occur with Wilms’ tumours but with neuroblastoma, an important differential diagnosis, due to catecholamine production from the tumour which originates from the adrenal medulla. Catecholamines can be detected in urine samples.
James is an 8-year-old boy who recently attended accident and emergency with a swollen left ankle. He had an x-ray and was discharged home and told there was no fracture. He has now developed a dark purple rash on his legs, which does not disappear with a glass pressed on. He was brought back to the department today vomiting, with abdominal pain. His observations and urine dipstick are all within normal limits. What is the most likely diagnosis?
A. Diabetic ketoacidosis
B. Viral gastroenteritis
C. Meningococcal sepsis
D. Idiopathic thrombocytopenic purpura
E. Henoch–Schönlein purpura
E. Henoch–Schönlein purpura
5 E Henoch–Schönlein purpura (E) is a diagnosis based on a set of symptoms including arthralgia, rash (urticarial to purpuric), abdominal pain and renal involvement (hypertension, nephrotic syndrome). It is a common paediatric condition affecting 3–10 year olds and usually follows a viral illness. It is a vasculitis process which can cause severe gastrointestinal and renal complications but is usually benign and self-limiting. Any child with abdominal pain and vomiting should have their glucose checked as they may be presenting for the first time with diabetic ketoacidosis (A). Viral infections can precipitate a reactive arthritis, though this follows the primary infection (B). Meningococcal sepsis (C) is always a concern in children with a purpuric rash and this must be considered and excluded and, in this case, is less likely with the normal heart rate, blood pressure and respiratory rate (observations within normal limits). Idiopathic thrombocytopenic purpura (D) may present with the rash, but the other symptoms are unusual with this condition and the platelet count would be low, whereas in Henoch–Schönlein purpura the platelet count is normal.
A 7-year-old boy presented to accident and emergency with diarrhoea and vomiting for the past week. He had no history of foreign travel and but had been to a zoo recently on a school trip. He was discharged home, after providing a stool sample, with rehydration advice as he was less than 5 per cent dehydrated and tolerating oral fluids. The stool had grown ‘Escherichia coli 0157’ which was phoned from the microbiology laboratory to the on-call doctor 48 hours later. What is the most serious complication?
A. Acute kidney injury
B. Haemolytic uraemic syndrome
C. Severe hypernatraemic dehydration
D. Henoch–Schönlein purpura
E. Post-gastroenteritis syndrome
B. Haemolytic uraemic syndrome
6 B Haemolytic uraemic syndrome (B) is a serious complication of particularly
E. coli and Shigella gastroenteritis. It is caused by a verocytotoxin produced by these bacteria which initiates an inflammatory reaction in vascular endothelium and neutrophil activation. It is recognized by a triad of microangiopathic haemolytic anaemia, acute kidney injury and thrombocytopenia. The morbidity and mortality results from the renal impairment which may require dialysis or progression to chronic kidney disease (A). Children with severe gastroenteritis of any cause may suffer from dehydration and if water loss is greater than salt loss, this may cause hypernatraemia (C). Children may also suffer with food intolerances (i.e. lactose intolerance) after an episode of gastroenteritis due to damage to the mucosal enzyme activity (E). Henoch–Schönlein purpura often follows a viral infection and is characterized by arthralgia, purpuric rash on the extensor surfaces of the lower limbs, abdominal pain and renal involvement (D).
A 5-year-old girl was brought to hospital at midnight by her mother with 5 per cent partial thickness burns to her chest and abdomen. Her mother states that she pulled on the kettle at 2 pm and the boiling water scalded her. On examination she is tachycardic, and drowsy with cool peripheries. Her initial blood tests: sodium 150 mmol/L, potassium 7.8 mmol/L, urea 10.2 mmol/L, creatinine 104 μmol/L, haemoglobin 14 g/dL. What is the most likely aetiological factor to account for these results?
A. Post-renal cause of acute kidney injury
B. Poisoning
C. Renal cause of acute kidney injury
D. Dehydration
E. Pre-renal cause of acute kidney injury
E. Pre-renal cause of acute kidney injury
7 E This girl has presented with a scald injury. The accident happened 10 hours before presentation which may arouse suspicion of non-accidental injury, but at present the more concerning feature is the acute kidney injury in a child with clinical shock. Burns damage the protective skin barrier, which allows excessive fluid and electrolyte loss. She may have been losing fluid through the damaged skin during the day, causing worsening dehydration (D); however she is now so fluid depleted that she has pre-renal acute kidney injury and hypovolaemia (E). This may subsequently result in acute tubular necrosis and thus a renal cause of acute kidney injury (C), but the primary cause is (E). The high sodium and haemoglobin would also support the diagnosis. Causes of post-renal acute kidney injury (A) are obstructive, such as ureteric stones, bladder outflow obstruction and neuropathic bladder. Poisoning (B) should be considered in children with drowsiness, especially in the context of non-accidental injury, and clues in the history such as access to illicit substances or medicines.
A 10-day-old baby boy was brought to accident and emergency with a distended abdomen. On questioning, he was born at term with no antenatal concerns. Until 2 days ago he had been feeding well and not vomiting, he had been wetting nappies, but mother has not witnessed a good urinary stream. On examining the child, you find a mass, dull to percussion, arising out of the pelvis, and he has had no wet nappies for the last day. You suspect he may have posterior urethral valves. Which one test will help to diagnose this underlying condition?
A. DMSA scan
B. Renal biopsy
C. Computed tomography (CT) abdomen
D. Micturating cystourethrogram
E. Renal ultrasound
D. Micturating cystourethrogram
8 DThis presentation of an enlarged, palpable bladder and anuria for 24 hours is suggestive of bladder outflow obstruction. This, in conjunction with a poor urinary stream, would make the diagnosis of posterior urethral valves likely. This is diagnosed using micturating cystourethrogram (D). DMSA (A) and renal biopsy (B) would provide information about the kidney. CT abdomen (C) would image the enlarged, fluid-filled bladder but possibly not the urethral valves. Renal ultrasound (E) will show the enlarged bladder and possibly show evidence of hydroureter and hydronephrosis with backflow from the bladder.
A 12-year-old boy who was born with multicystic dysplastic kidneys. He had a renal transplant when he was 7 years old due to chronic kidney disease stage V after having peritoneal dialysis for 1 year. Which of the following would you not expect him to be taking?
A. Septrin
B. Tacrolimus
C. Diclofenac
D. Growth hormone
E. Erythropoietin
C. Diclofenac
9 C After renal transplantation there are many medications that are required. These children are susceptible to opportunistic infections and septrin (A) is used as prophylaxis to Pneumocystis carinii (Pneumocystis jiroveci), they are also particularly at risk of cytomegalovirus, varicella zoster virus and fungal infection. Immunosuppression is necessary to avoid rejection of the transplanted organ, including tacrolimus (B), ciclosporin and mycophenolate mofetil. Children with chronic renal disease may have impaired growth which can respond to growth hormone (D). They are often anaemic due to defective renal erythropoietin production and supplementation is beneficial (E). Diclofenac (C) should not be used in renal impairment as it and other non-steroidal anti-inflammatory drugs are nephrotoxic.
An 11-year-old girl presents to the out of hours GP while on holiday in England with abdominal pain. She tells you she has polycystic kidney disease which was diagnosed early in life. She has bilateral palpable kidneys and hepatosplenomegaly, with visible distended veins on the abdomen and ascites. Abdominal ultrasound shows liver fibrosis. What is the inheritance of this condition?
A. Autosomal dominant
B. X-linked
C. Sporadic mutation
D. Autosomal recessive
E. Microdeletion
D. Autosomal recessive
10 D This girl has polycystic kidney disease, of which there are two types. The autosomal recessive type (D) presents in childhood with bilateral renal masses, respiratory distress due to pulmonary hypoplasia and congenital hepatic fibrosis with pulmonary hypertension. It is due to tubular dilatation of the distal collecting system. Renal function is impaired and progressively deteriorates, requiring renal replacement therapy (dialysis or transplant). The autosomal dominant (A) type may present in older children or adults. The cysts are grossly dilated nephrons which compress normal renal tissue. It affects renal, liver and cerebral vasculature.
