[Music] all right next is renal so white blood cell casts in your in the two big ones I want you to think about are acute interstitial nephritis and pyelonephritis so uremia so that's from kidney disease where the urea levels are really high it can impair utley lip function so this can cause an increased bleeding time but there are four manifestations of the uremia that I want you to remember that are indications for dialysis so one is hemolytic uremic syndrome which is a form of microangiopathic hemolytic anemia remember that this is where you get the platelets clumping and then the red blood cells going by and then they shear which causes thrombocytopenia and a mini-me oh that's hu s which can also be precipitated by Antero hemorrhagic you coli heck which is associated with eating undercooked burgers and then and usually people with a heck when they're treated with antibiotics leches fluoroquinolones will lead to H us but uremia can also lead to H us the second is uremic pericarditis people have chronic kidney disease with pericarditis that's you riemeck pericarditis platelet dysfunction so they can have elevated bleeding times and if they start bleeding out or confusion which is just called uremia and they would have asterixis with that those are the manifestations of uremia and all of those are treated with dialysis the top two causes of CKD or hypertension and diabetes mellitus so um remember we're gonna talk about other dialysis indications and the mnemonic is a e i o u so acidosis which is a refractory electrolytes hyperkalemia that's also refractory intoxications as in fluid overload from CKD and uremia symptoms so the intoxications there's a sub mnemonic which is mail which is methanol aspirin lithium and ethylene glycol those four substitute substances when you're intoxicated with them those are also die Eliza bull so acute interstitial nephritis I want you to remember and said diuretics and antibiotics this is an allergic reaction to medications the mnemonic is fear fever yoson Ophelia azo tamiya meaning kidney injury and rash so when I think of a cute interstitial nephritis I think of someone who recently took drugs and now they have hematuria with white blood cell casts remember white blood cell casts you'll see an either acute interstitial nephritis or pyelonephritis so when I see white blood cell casts that kind of makes me suspicious right away and then if they have a rash on top of that it's a it's a grand-slam this is a cute interstitial nephritis versus acute tubular necrosis which can be caused by hypoxia or toxins when you are hypoxic or there's under perfusion so the kidney is safe that patient went into shock so they had pre renal azo tv-out remember if the buin create an M ratio is greater than 20 that's pre renal SOT Mia if there's not enough blood flow reaching the kidneys then the tubules can dry up Anna Krause and that's called acute tubular necrosis certain toxins can do this as well but the classic vignette is someone who went into shock and later developed acute kidney injury and so the key here is on microscopic your analysis you will see muddy brown casts and then this is just treated with IV fluids next is the renal tubular acidosis so remember when you metabolic acidosis the first thing you want to do is check whether the anion gap is this the anion gap metabolic acidosis or not anion gap metabolic acidosis the anion gap everyone knows the mnemonic mud piles methanol uremia DKA propylene glycol isoniazid lactic acidosis ethylene glycol and salicylates but non an eye on gap metabolic acidosis people tend to just um get lost on it but it's so just keep it simple the two most common causes of non anion gap metabolic acidosis are diarrhea because you poop out all the bicarb so that makes you acidotic or the next most common one is the rtas renal tubular acidosis and it's not that hard there's three types you need to know RTA type 1 type 2 and type 4 so RTA type 1 number 1 should remind you of one letter H H should remind you of hydrogen so type 1 is due to under excretion of hydrogen you lock up all the hydrogen so you get acidotic one should also remind you of stones so kidney stones has the letter you have to spell stone by spelling one st o n e so RTA type 1 is associated with kidney stones type 2 2 should remind you by b.i - by that's bicarb you cannot absorb bicarb properly so you lose a lot of bicarb that makes you acidotic type 4 four letters should remind you of a LD o l dosterone so this is hypoalle dose grown so hyponatremia hyperkalemia remember with aldosterone it actually people always remember you increase you absorb sodium index potassium but people always forget that aldosterone action also excretes hydrogen as well through the Alpha intercalated cells and so when you lose all that hydrogen you become alkalotic but that's when aldosterone is working but this is hypoalle dosterone ism so all the hydrogen gets kept so that makes you acidotic and the key thing here is that's the only one that has hyperkalemia so with those little kickers that should help you if there's kidney stones non at anion gap metabolic acidosis RTA type 1 if there's a non anion gap metabolic acidosis with hyperkalemia that's type 4 if it's not neither of those probably type 2 and then remember if you have a metabolic alkalosis what's the next best step the next best step is to check the urine chloride why because if the chloride is high right the urine chloride is high that means the kidneys are unable to absorb chloride so this is a kidney problem and if the urine chloride is low then this is most likely another problem a GI problem such as vomiting and you vomit out all the acids so you get alkalotic remember that steatorrhea so fatty stools when it reaches the terminal ileum this can bind up the calcium this is also known as saponification and when it binds up the calcium remember that this is a cool concept because oxalate and calcium tend to bind at the terminal ileum and then that makes it insoluble so you poop it out calcium oxalate but if the fat is stealing all the calcium and binding to it then oxalate has nothing to bind to and it's still soluble so it gets reabsorbed and goes to the kidneys instead when it goes to the kidneys it finds another friend it finds calcium and the tubules so that will make calcium oxalate in the kidney tubules become insoluble and make kidney stones so basically eating high fat foods predisposes to calcium oxalate kidney stones also this is a trick tricky one too as sometimes people ask with calcium oxalate stones do you want to increase calcium uptake or decrease calcium uptake because people think Oh calcium oxalate stones or if you eat a lot of calcium that'll make more calcium oxalate stones that's not true when you eat when you eat a lot of calcium the calcium goes to the terminal ileum same thing it'll bind up all the oxalate and then you'll be able to poop out all the calcium oxalate if you have a low calcium diet then that oxalate is free to go back and reabsorb back into the kidneys and make calcium oxalate stones there so basically my point is if someone has kidney stones you want to have a low salt diet a low fat diet and a high calcium diet and also drink a lot of water to make the crystals more soluble an elderly male who smokes a lot who has gross painless hematuria I want you to think about two things either renal cell carcinoma or a bladder cancer renal cell carcinoma the person will also on top of the hematuria will also have a flank pain and abdominal mass if that's true the next thing what you want to do is a CT of the abdomen and then treat it with a nephrectomy but if the person doesn't have an abdominal mass or flank pain then the next thing you should think about is bladder cancer and it's most likely transitional cell carcinoma this is due to the carcinogens and cigarette smoke the carcinogens are trapped in the urine a lot and it tends to pool in the bladder and that can cause cancer and then if you suspect bladder cancer which is gross painless hematuria in a chronic smoker without any signs of renal cell carcinoma so no abdominal or flank pain then the next best step is a cystoscopy next is a young male with irregularly shaped testicle a painless mass and the testicle what's the next best step is a scrotal ultrasound you want to see if the if that's actually amassed the mass could be a potential cancer the next step is an inguinal orchiectomy you don't want to biopsy it because of potential seeding of the scrotum so if it's basically diagnosed on ultrasound and then you're just gonna remove it testicular torsion versus epididymitis they like to compare these so remember that testicular torsion is when you get twisting of around the spermatic cord and it cuts off the blood supply this is an acute onset of severe testicular pain but the cord the spermatic cord is non-tender if you elevate the scrotum it's worse with elevation and the key distinguishing factor here is the cremasteric reflex if you stroke the medial aspect of the upper thigh the scrotum nor under normal conditions will raise but in this one that reflex is absent whereas in epididymitis it's present another key distinction is epididymitis is an infection so this person will also have fever but their cord will be tender and also upon elevation its relieved so those are the differences but if I had to remember the key differences is epididymitis will have a fever and then a testicular torsion has no cream aesthetic reflex and if you're unsure about the diagnosis of testicular torsion like in the vignette the picture is not very clear and they ask what's the best next step then you want to do a scrotal ultrasound see there might be mixed features but if it's very clear the diagnosis is clear-cut and there's no predicting and that's what I mean by clear-cut if all the facts are textbook but if one of the facts kind of doesn't go with it like maybe um the patient has no cremasteric reflex but they have a fever and when you raise the scrotum it's the pain is relieved so there's contradictory information then what they want you to know is what the the next diagnostic test is would be a scrotal ultrasound a Doppler to check for blood flow or to narrow the differentials if it's very clear then the next step is um or key OPEC sea so surgery and you want to do bilateral or keep X because the other one will most likely towards as well sometime in the future epidural mitos is also I wanna compare and contrast that with or T itis right testicular inflammation of the testicles versus prostatitis so the three of those are all kind of can all get inflamed and in a young person the difference is between a young person and the old person so a young person the main culprits will be gonorrhea and chlamydia and in an older person the main culprit will be e coli so you treat them with different antibiotics by young it's like someone less than 35 and by older like older than 35 and and sexual history helps too so a young person you're gonna give such ceftriaxone and as a throw my son and an older person you want to treat with a fluoroquinolone