foreign [Applause] [Music] ers.com in this video I'm going to be going through lower urinary tract infections and you can find written notes on this topic at xerifinals.com lower UTI or in the Urology section of the zero to finals surgery book so let's jump straight in lower urinary tract infections or UTIs involve infection in the bladder causing cystitis which is inflammation of the bladder they can spread up to the kidneys and cause pyelonephritis which is inflammation and infection in the kidney urinary tract infections are far more common in women where the urethra is much shorter making it easier for bacteria to get into the bladder the primary source of bacteria for urinary tract infections is from feces normal intestinal bacteria such as E coli can easily make the short Journey to the urethral opening from the anus sexual activity is a crucial method for spreading bacteria around the perineum incontinence and poor hygiene can also contribute to the development of UTIs urinary catheters are also a key source of infection and catheter-associated urinary tract infections tend to be more significant and challenging to treat let's talk about the presentation a typical lower urinary tract infection presents with dysuria which is pain stinging or burning when passing urine suprapubic pain or discomfort urinary frequency urinary urgency incontinence of urine hematuria which is blood in the urine cloudy or foul smelling urine and confusion which is commonly the only symptom in older or frail patients a Tom tip for you it's important to distinguish between patients who have a lower urinary tract infection and those with pyelonephritis pyelonephritis is generally a more serious condition with significant complications including sepsis and kidney scarring suspect pylonephritis in patients with a fever loin or back pain nausea or vomiting and renal angle tenderness on examination let's talk about urine dipstick testing on a urine dipstick you can test for nitrites gram-negative bacteria such as E coli breakdown nitrates which are a normal waste product in urine into nitrites the presence of nitrites suggests bacteria in the urine you can also test for leukocytes which are white blood cells it's normal to have a small number of leukocytes in the urine but a significant rise can result from an infection or other causes of inflammation leukocyte esterase is what's tested on a urine dipstick and this is a product of leukocytes and indicates the number of leukocytes in the urine red blood cells in the urine indicates blood microscopic hematuria is where blood is identified on a urine dipstick but not seen when looking at the sample macroscopic hematuria is when blood is seen in the urine it's visible inside the urine hematuria 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 from 2020 suggest that the presence of nitrites or leukocytes plus red blood cells indicate that the patient is likely to have a UTI if both nitrites and leukocytes are present the patient requires treatment for a UTI if only nitrites are present it's worth treating as a UTI if only leukocytes are present the patient should not be treated as a UTI unless there's clinical evidence that they have one a Midstream urine or MSU sample can be sent to the lab for microscopy culture and sensitivity testing which will help determine the infective organism and the antibiotics that will be effective in treatment not all patients with an uncomplicated UTI require an MSU to be sent to the lab but it is important in pregnant patients patients with recurrent UTIs patients with atypical symptoms or when the symptoms do not improve with antibiotics let's talk about the causes of lower urinary tract infections the most common cause of a UTI is escherichia coli E coli are gram-negative anaerobic rod-shaped bacteria that are part of the normal lower intestinal microbiome they're commonly found in feces and can easily spread to the bladder other causes of lower urinary tract infections are klebsiella pneumoniae which is a gram-negative anaerobic rod enterococcus species pseudomonas eryginosa staphylococcus saprophyticus and candida albicans which is a fungus let's talk about the antibiotic choice always follow the local guidelines an appropriate initial antibiotic in the community would be trimethoprim however this is often associated with high rates of bacterial resistance and nitrofurantoin which needs to be avoided in patients with renal impairment and an egfr of less than 45. alternative choices are pivmacillinam amoxicillin and cephalexin let's talk about urinary tract infections in pregnancy in pregnant women urinary tract infections increase the risk of pyelonephritis premature rupture of membranes and preterm labor the management is slightly different in pregnancy urinary tract infections in pregnancy require seven days of antibiotics all women should have a Midstream urine sent to the lab for microscopy culture and sensitivity testing the antibiotic options are nitrofurantoin however this needs to be avoided in the third trimester amoxicillin but only after sensitivities are known or cephalexin nitrofurantoin needs to be avoided in the third trimester as there's a risk of neonatal hemolysis or destruction of the neonatal red blood cells trimethoprim needs to 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 which is why we give pregnant women folic acid supplementation trimethoprim in early pregnancy can cause congenital malformations particularly neural tube defects such as spina bifida it's not known to be harmful later in pregnancy but is generally avoided and less necessary if you like this video consider joining the zero to finals patreon account where you get early 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