Zero To Finals

Question 1

Presentation of a lower urinary tract infection

Answer 1

Presentation
Lower urinary tract infections present with:
• Dysuria (pain, stinging or burning when passing urine)
• Suprapubic pain or discomfort
• Frequency
• Urgency
• Incontinence
• Haematuria
• Cloudy or foul-smelling urine
• Confusion is commonly the only symptom in older and frail patients

Question 2

Pylelonephritis presentation

Answer 2

Pyelonephritis has a similar presentation to lower urinary tract infections plus the additional triad of symptoms:
○ Fever
○ Loin or back pain (bilateral or unilateral)
○ Nausea or vomiting

	Patients with pyelonephritis may also have:
		§ Systemic illness
		§ Loss of appetite
		§ Haematuria
		§ Renal angle tenderness on examination

Question 3

Urine dipstick in lower UTI diagnosis

Answer 3

Nitrites on a dipstick test suggest bacteria in the urine. Gram-negative bacteria (e.g., E. coli) break down nitrates (a normal waste product in urine) into nitrites.

Leukocytes are white blood cells. It is normal to have a small number of leukocytes in the urine, but a significant rise can result from an infection or other cause of inflammation. Leukocyte esterase (a product of leukocytes) is tested on a urine dipstick, indicating the number of leukocytes in the urine.

Red blood cells in the urine indicate bleeding. Microscopic haematuria is where blood is seen on a urine dipstick but not seen when looking at the sample. Macroscopic haematuria is where blood is visible in the urine. Haematuria is a common sign of infection but can also be present with other causes, such as bladder cancer or nephritis.

Nitrites are a better indication of infection than leukocytes. The NICE clinical knowledge summaries (June 2023) suggest that nitrites or leukocytes plus red blood cells indicate that the patient will likely have a UTI. The dipstick result is less reliable in catheterised patients or women over 65.
Where only nitrites are present, it is worth treating as a UTI. Where only leukocytes are present, a sample should be sent to the lab for further testing. Antibiotics may be considered where there is clinical evidence of a UTI.

A midstream urine (MSU) sample sent for microscopy, culture and sensitivity testing will determine the infective organism and the antibiotics that will be effective in treatment. Not all patients with an uncomplicated UTI require an MSU. An MSU is important in:
• Pregnant patients
• Patients with recurrent UTIs
• Atypical symptoms
• When symptoms do not improve with antibiotics

Question 4

Common causes of lower UTI

Answer 4

Causes
The most common cause of UTI is Escherichia coli, which are gram-negative, anaerobic, rod-shaped bacteria. They are part of the lower intestinal microbiome and can easily spread from faeces to the bladder.
Other causes:
• Klebsiella pneumoniae (gram-negative, anaerobic, rod-shaped bacteria)
• Enterococcus
• Pseudomonas aeruginosa
• Staphylococcus saprophyticus
• Candida albicans (fungal)

Management of Lower Urinary Tract Infections
Follow local guidelines. An appropriate initial antibiotic in the community would be:
	○ Nitrofurantoin (avoided in patients with an eGFR <45)
	○ Trimethoprim (often associated with high rates of bacterial resistance)
	 
	Alternatives:
		§ Pivmecillinam
		§ Amoxicillin
		§ Cefalexin
		 
		The typical duration of antibiotics is:
			□ 3 days of antibiotics for simple lower urinary tract infections in women
			□ 5-10 days of antibiotics for immunosuppressed women, abnormal anatomy or impaired kidney function
			□ 7 days of antibiotics for men, pregnant women or catheter-related UTIs
			 
			It is worth noting that NICE recommend changing the catheter when someone is diagnosed with a catheter-related urinary tract infection.

Question 5

Management of lower UTI

Answer 5

Management of Lower Urinary Tract Infections
Follow local guidelines. An appropriate initial antibiotic in the community would be:
○ Nitrofurantoin (avoided in patients with an eGFR <45)
○ Trimethoprim (often associated with high rates of bacterial resistance)

	Alternatives:
		§ Pivmecillinam
		§ Amoxicillin
		§ Cefalexin
		 
		The typical duration of antibiotics is:
			□ 3 days of antibiotics for simple lower urinary tract infections in women
			□ 5-10 days of antibiotics for immunosuppressed women, abnormal anatomy or impaired kidney function
			□ 7 days of antibiotics for men, pregnant women or catheter-related UTIs
			 
			It is worth noting that NICE recommend changing the catheter when someone is diagnosed with a catheter-related urinary tract infection.

Question 6

Management of Pyelonephritis

Answer 6

Management of Pyelonephritis
Referral to hospital is required if there are features of sepsis or if it is unsafe to manage them in the community.
NICE guidelines (2018) recommend the following first-line antibiotics for 7-10 days when treating pyelonephritis in the community:
• Cefalexin
• Co-amoxiclav (if culture results are available)
• Trimethoprim (if culture results are available)
• Ciprofloxacin (keep tendon damage and lower seizure threshold in mind)

Patients admitted to hospital with sepsis require the sepsis six, which includes a serum lactate, blood cultures, urine output monitoring, oxygen, empirical broad-spectrum antibiotics and IV fluids.
Two things to keep in mind with patients that have significant symptoms or do not respond well to treatment are:
	○ Renal abscess
	○ Kidney stone obstructing the ureter, causing pyelonephritis

Question 7

Risks of having a UTI during pregnancy

Answer 7

Pregnancy
Urinary tract infections in pregnancy increase the risk of pyelonephritis, premature rupture of membranes and pre-term labour.

Question 8

Management of a UTI in pregnancy

Answer 8

Management in Pregnancy
Urinary tract infection in pregnancy requires 7 days of antibiotics. All women should have an MSU for microscopy, culture and sensitivity testing.
The antibiotic options are:
• Nitrofurantoin (avoided in the third trimester)
• Amoxicillin (only after sensitivities are known)
• Cefalexin (the typical choice)

Nitrofurantoin should be avoided in the third trimester as there is a risk of neonatal haemolysis (destruction of the neonatal red blood cells).
Trimethoprim should be avoided in the first trimester as it works as a folate antagonist. Folate is essential in early pregnancy for the normal development of the fetus. Trimethoprim in early pregnancy can cause congenital malformations, particularly neural tube defects (e.g., spina bifida). It is not known to be harmful later in pregnancy but is generally avoided unless necessary.

Question 9

What is an upper UTI?

Answer 9

Upper UTI: infection of the kidney (pyelonephritis)

Question 10

What is an uncomplicated UTI?

Answer 10

Uncomplicated UTI: if occurring in healthy non-pregnant adult women

Question 11

What is a complicated UTI?

Answer 11

Complicated UTI: the presence of factors that increase the risk of treatment failure (e.g diabetes, structural abnormalities, catheter and other devices and all UTIs in men)