The kidney is particularly susceptible to some toxicants at doses which if not safe are at least less toxic to other organs. What puts the kidneys at risk for the hydrophilic toxicants/metabolites that wind up in the kidneys?

A. Area is the highest

B. Bioactivation is the highest

C. Concentration is the highest

D. Damage repair is the lowest

Answer: C A can be eliminated. While filtering function means kidneys have a larger surface area than a solid organ would, the lungs with alveoli and intestines with microvilli have larger surface areas. B. The liver has greater bioactivation potential and acts as the main organ for metabolizing a wide range of endogenous (e.g., sex hormones) and exogenous (e.g., pharmaceuticals, pesticides). D can be eliminated as organs such as the heart and the brain have far less capacity to repair damage.


What is the most common site of toxicant induced kidney damage? 

A. Glomerulus 

B. Loop of Henle/distal tubule 

C. Papilla 

D. Proximal tubule

Answer: D. This one is not really set up to eliminate the other answers so much as remembering what the proximal tubules do and knowing how their role in removing water and concentrating urine acts to concentrate toxicants in the urine too.


The U.S. Preventative Services Task Forces has in progress a chronic kidney disease draft research plan. While the kidneys have greater repair capacity than some organs (e.g., heart, brain) chronic kidney damage is often irreversible. Earlier detection and interventions could preserve significant kidney function for some at risk patients. Chronic kidney disease is classified by increased amount of protein in the urine and decreased glomerular filtration rate. Part of the draft research plan involves exploring the risks and benefits of increased screening using biomarkers of glomerular function in asymptomatic individuals. What biomarkers are currently part of this draft research plan?

A. Albumin and creatine kinase

B. Alanine aminotransferase (ALT) and CK-18

C. Amounts of Brain Natriuretic Peptide (BNP) and cardiac troponins

D. Autoantibodies and C-Reactive Protein (CRP)


Answer: A Notes: Answer B biomarkers are used for liver damage monitoring. Answer C biomarkers is used for cardiac damage with BNP being released to help regulate blood pressure which goes down in response to the heart not working as efficiently or effectively. Answer D biomarkers are used to look for general immune system damage to self and is not organ inherently organ specific although some autoimmune conditions (e.g., lupus nephritis) can be very damaging to the kidneys.


A patient starts taking many times the recommended amount of their medication. This drug has more than one effect but is type of analgesic. The patient goes to the hospital and reports their symptoms. What of the following drug and symptom combinations are most likely to be matched. 

A. Aspirin and acute kidney failure and bloody urine

B. Bleeding and metabolic acidosis while taking acetaminophen (aka paracetamol)  

C. Codeine and respiratory depression and sleepiness 

D. Diethylene glycol and icterus (i.e., jaundice) and high liver enzyme levels (e.g., ALT, AST) 


Answer: C. Notes: Aspirin is more likely to cause bleeding and metabolic acidosis. Acetaminophen is more likely to cause icterus and high liver enzymes. Diethylene glycol is an adulterant which leads to the formation of crystals causing acute kidney failure and bloody urine. In terms of analgesics which are associated with kidney damage, the NSAIDs interact with kidney blood flow and pressure and can damage the kidneys particularly in the presence of other medications or already limited kidney function.


C&D Ch. 3 9th table 3 describes many different ultimate toxicants and their sources. Oxalic acid forms calcium oxalate which precipitates and damages the kidneys. Where does it come from?

A. Acetaminophen

B. Amygdalin

C. Ethanol

D. Ethylene glycol


Answer: D. Notes: Acetaminophen has NAPQI as ultimate toxicant which is primarily formed in and damages the liver. Amygdalin forms cyanide which poisons all parts of the body. Ethanol itself acts as a toxicant without bioactivation and while its conversion into acetaldehyde can cause flushing and discomfort the further metabolism into acetic acid is largely a detoxification reaction. This is in sharp contract with methanol where its metabolism can cause blindness and death.