Disorders of the Excretory System Questions in English

(B) In the process of hemodialysis,blood is taken out from an artery $(P)$ of the patient.
To prevent blood clotting within the dialyzing machine,an anticoagulant called heparin $(Q)$ is added to the blood.
After the blood is purified in the dialyzing unit,an anti-heparin $(R)$ is added to restore the normal clotting ability of the blood.
Finally,the purified blood is returned to the patient's body through a vein $(S)$.

(B) Gout is a type of arthritis that occurs due to the accumulation of uric acid crystals in the joints.
When the body produces too much uric acid or the kidneys excrete too little,it builds up in the blood and forms needle-like crystals in a joint or surrounding tissue,causing pain,inflammation,and swelling.
Therefore,the correct option is $B$.

(D) Diabetes mellitus is a metabolic disorder characterized by high blood glucose levels (hyperglycemia).
When blood glucose levels exceed the renal threshold,glucose is excreted in the urine,a condition known as Glycosuria.
Additionally,due to the inability of cells to utilize glucose,the body breaks down fats,leading to the accumulation of Ketone bodies in the urine (Ketonuria).
Uremia,on the other hand,refers to the accumulation of urea in the blood,which is a symptom of kidney failure,not diabetes mellitus.
Therefore,both Glycosuria and the presence of Ketone bodies in urine are indicative of diabetes mellitus.

(C) Hemodialysis is a procedure used to remove excess urea and other nitrogenous wastes from the blood of patients with kidney failure.
$1$. During this process,blood is drained from a convenient artery (not a vein) and pumped into a dialysing unit.
$2$. The dialysing unit contains a coiled cellophane tube surrounded by a dialysing fluid,which has the same composition as plasma except for the nitrogenous wastes.
$3$. The cellophane membrane is porous,allowing the passage of molecules based on concentration gradients,thus facilitating the removal of urea and other wastes.
$4$. Therefore,statement $C$ is correct,while others are incorrect because blood is taken from an artery,the membrane is porous,and hemodialysis is primarily for kidney failure,not liver failure.

$(A)$ The correct matches are as follows:
$1$. Renal calculi: These are stones or insoluble masses of crystallized salts (like oxalates) formed within the kidney. Thus, $A-ii$.
$2$. Renal failure: This is the condition where kidneys stop functioning, often treated by kidney transplantation. Thus, $B-iii$.
$3$. Glomerulonephritis: This refers to the inflammation of the glomeruli of the kidney. Thus, $C-i$.
$4$. Uremia: This is the accumulation of urea in the blood due to kidney malfunction. Thus, $D-iv$.
Therefore, the correct sequence is $A-ii, B-iii, C-i, D-iv$.

(D) Acute renal failure occurs when the kidneys suddenly lose their ability to filter waste products from the blood.
While haemodialysis is a temporary procedure used to filter blood when kidneys fail,it does not cure the underlying condition.
Kidney transplantation is considered the ultimate or permanent method for the correction of renal failure,as it replaces the non-functional kidney with a healthy donor kidney,restoring normal renal function.

(D) Oliguria is defined as a reduced volume of urine production. In clinical pediatrics,oliguria is typically defined as a urine output of less than $0.5 \text{ ml/kg/h}$ in children. This condition often indicates underlying renal dysfunction,dehydration,or other systemic issues that require medical evaluation.

(B) The correct matching is as follows:
$1$. Nephritis: Inflammation of the nephrons often leads to the leakage of proteins into the urine,known as $b$. Proteinuria.
$2$. Chronic kidney disease: Long-term damage leads to the scarring and shrinkage of the organs,resulting in $c$. Reduced kidney size.
$3$. Acute renal failure: $A$ sudden decline in kidney function often manifests as $a$. Oligouria (decreased urine output).
$4$. Kidney stones: The presence of mineral deposits can cause inflammation and the presence of crystals or debris,leading to $d$. Hazy urine.
Therefore,the correct sequence is $1-b, 2-c, 3-a, 4-d$.

(A) Albuminuria refers to the presence of excessive albumin,a type of protein,in the urine.
Normally,the glomerular filtration membrane prevents large molecules like proteins from passing into the filtrate.
When the endothelial-capsular membrane (glomerular filtration barrier) is damaged,often due to high blood pressure (hypertension) or kidney disease,these proteins leak into the urine.
Therefore,it indicates injury to the glomerular filtration membrane.

(D) Acute renal failure refers to the sudden loss of kidney function.
$A$. Severe bleeding leads to hypotension and reduced blood flow to the kidneys (prerenal failure).
$B$. Acute obstruction of both ureters prevents urine outflow,causing backpressure and kidney damage (postrenal failure).
$C$. Nephrotoxic drugs directly damage the renal tubules (intrinsic renal failure).
$D$. Deficiency of $ADH$ (Antidiuretic Hormone) leads to Diabetes Insipidus,which causes excessive dilute urine production and dehydration,but it does not cause acute renal failure.

(C) Statement $I$ is correct because peritoneal dialysis is a portable method that allows patients to perform the procedure themselves at home,at work,or while travelling.
Statement $II$ is incorrect because haemodialysis is generally considered more efficient than peritoneal dialysis in terms of clearing solutes and waste products from the blood in a shorter duration.
Therefore,Statement $I$ is correct and Statement $II$ is incorrect.

(C) Acute renal failure $(ARF)$ is a condition where the kidneys suddenly lose their ability to filter waste products from the blood.
Biochemically,this is primarily detected by an elevated level of creatinine in the blood (serum creatinine),which indicates that the kidneys are not filtering waste effectively.
While the question mentions 'in urine',in clinical practice,the accumulation of creatinine in the blood is the hallmark diagnostic marker for $ARF$.
Among the given options,elevated serum creatinine is the standard diagnostic indicator for renal dysfunction.

(A) In haemodialysis,the patient's blood is drained from a convenient artery and pumped into a dialysing unit called an artificial kidney.
During this process,the blood is passed through a coiled cellophane tube,which acts as a semipermeable membrane.
This tube is immersed in a dialysing fluid (dialysate) that has the same composition as plasma except for the nitrogenous wastes.
Due to the concentration gradient,nitrogenous wastes move out of the blood into the dialysing fluid through the cellophane membrane.

(C) The correct matching is as follows:
$1$. Calcium stones $(A)$ are primarily composed of calcium oxalates $(II)$.
$2$. Struvite stones $(B)$ are formed in response to urinary tract infections caused by urea-splitting bacteria $(III)$.
$3$. Uric acid stones $(C)$ are often associated with a high protein diet $(IV)$.
$4$. Cystine stones $(D)$ are caused by a rare genetic disorder known as cystinuria $(I)$.
Therefore,the correct sequence is $A-II, B-III, C-IV, D-I$.

(B) Cystinuria is a hereditary (genetic) disorder characterized by the inability of the renal tubules to reabsorb the amino acid cystine.
As a result,high concentrations of cystine are excreted in the urine.
Because cystine is poorly soluble in urine,it crystallizes and forms stones (calculi) in the kidneys,ureters,or bladder.
Therefore,the formation of cystine stones is primarily due to a genetic defect in the transport mechanism of amino acids.

(D) Acute renal failure $(ARF)$ is a condition defined by a rapid and sudden decline in kidney function.
$i$. Incorrect: $ARF$ involves a decrease,not an increase,in the glomerular filtration rate $(GFR)$.
$ii$. Incorrect: $ARF$ often leads to oliguria (reduced urine output) or anuria,not the frequent elimination of large quantities of urine.
$iii$. Correct: $ARF$ is characterized by a sudden worsening or loss of renal function.
$iv$. Correct: Due to the inability of the kidneys to filter waste,there is an accumulation of nitrogenous wastes,leading to elevated serum creatinine and blood urea nitrogen $(BUN)$ levels.
Therefore,statements $iii$ and $iv$ are correct.

(D) Creatinine is a waste product produced by the muscles from the breakdown of a compound called creatine.
It is filtered from the blood by the kidneys and excreted in the urine.
When kidney function is impaired,the kidneys are unable to filter creatinine efficiently,leading to an accumulation of creatinine in the blood.
Therefore,elevated levels of blood creatinine are a standard clinical marker used to diagnose poor kidney function or renal failure.

(B) The symptoms described, including intermittent pain in the back and sides (flank pain) below the ribcage, hazy or pinkish (hematuria) urine, and pain during micturition (dysuria), are classic clinical indicators of $kidney stones$ (renal calculi).
$1$. $Kidney stones$ are hard deposits of minerals and salts that form inside the kidneys.
$2$. As these stones move through the urinary tract, they cause intense, intermittent pain.
$3$. The presence of blood in the urine (pinkish color) occurs due to the irritation or scratching of the lining of the ureters or bladder by the stones.
$4$. $Uremia$ refers to the accumulation of urea in the blood due to kidney failure.
$5$. $Diabetes mellitus$ is characterized by high blood glucose levels.
$6$. $Nephritis$ is the inflammation of the kidneys, which typically presents with different clinical features.

(D) Statement-$I$ is correct because hemodialysis is primarily used as a temporary life-saving procedure to remove metabolic wastes from the blood in patients with renal failure while they await a kidney transplant.
Statement-$II$ is incorrect because dialysis is often the only available life-sustaining treatment for patients who are not candidates for a renal transplant due to age, comorbidities, or other medical contraindications. Therefore, it serves as a supportive measure even for those who cannot undergo transplantation.

(D) Chronic kidney disease $(CKD)$ is characterized by a long-term,progressive loss of kidney function. $A$ key diagnostic feature that distinguishes $CKD$ from acute kidney injury $(AKI)$ is the physical size of the kidneys. In $CKD$,the kidneys typically appear shrunken or small on ultrasound due to long-standing fibrosis and scarring. In contrast,$AKI$ often presents with kidneys that are normal in size or even enlarged due to acute inflammation or edema.

(A) Struvite stones, also known as infection stones, are composed of magnesium ammonium phosphate $(MgNH_4PO_4 \cdot 6H_2O)$.
These stones form in the presence of urea-splitting bacteria, such as Proteus species, which produce the enzyme urease.
Urease hydrolyzes urea into ammonia and carbon dioxide.
The resulting increase in ammonia raises the urinary $pH$, creating an alkaline environment that promotes the precipitation of magnesium ammonium phosphate, leading to the formation of struvite stones.

(B) Kidney stones,also known as renal calculi,are hard deposits made of minerals and salts that form inside the kidneys.
Most kidney stones are composed of calcium compounds.
The most common type of kidney stone is calcium oxalate,followed by calcium phosphate.
These crystals form when the urine becomes concentrated,allowing minerals to crystallize and stick together.

(C) Uremia is a medical condition characterized by high levels of urea in the blood.
Normal blood urea levels typically range between $0.01$ to $0.03 \%$ $(10-30 \text{ mg/100 mL})$.
When the concentration of urea in the blood exceeds $0.03 \%$ (or $30 \text{ mg/100 mL}$),it is clinically referred to as uremia.
Therefore,the threshold value indicated in the context of this question is $0.0003$ (which corresponds to $0.03 \%$).

(C) Struvite stones,also known as infection stones,are primarily composed of magnesium ammonium phosphate.
$I$. $CORRECT$: They are formed in response to urinary tract infections (UTIs) caused by urease-producing bacteria (e.g.,Proteus species),which increase urine pH.
$II$. $INCORRECT$: They are not genetic disorders; they are secondary to infections.
$III$. $CORRECT$: Due to the rapid precipitation of minerals in alkaline urine,these stones grow quickly and can form large 'staghorn' calculi.
$IV$. $INCORRECT$: This is more characteristic of uric acid stones.
$V$. $INCORRECT$: This is characteristic of cystinuria,a genetic disorder.
Therefore,statements $I$ and $III$ are correct.

(A) $Uremia$ refers to the accumulation of urea in the blood.
This condition occurs due to the malfunctioning of the kidneys,which are unable to filter urea effectively from the bloodstream.