ANATOMY AND PHYSIOLOGY
KIDNEYS
The kidneys are two bean-shaped organs that are roughly the size of a fist. A tough, fibrous renal capsule
surrounds each kidney and provides support for the soft tissue inside. Beyond that, two layers of fat serve
as further protection. The adrenal glands lie on top of the kidneys. Inside the kidneys are a number of
pyramid-shaped lobes. Each consists of an outer renal cortex and an inner renal medulla. Nephrons flow
between these sections. Each nephron includes a filter, called the glomerulus, and a tubule. The
glomerulus filters blood, which enters the kidneys through the renal arteries and leaves through the renal
veins. The kidneys are relatively small organs, but they receive 20-25% Trusted Source of the heart’s
output. The tubule returns necessary substances to the blood and removes waste that then becomes urine.
The kidneys excrete urine through the ureter, a tube that leads to the bladder. The main role of the kidneys
is maintaining homeostasis. They manage fluid levels, electrolyte balance, and other factors that keep the
internal environment of the body consistent and comfortable. These organs carry out a wide range of
bodily functions. The kidneys remove waste and extra fluid from the body. The kidneys also remove acid
that is produced by the cells of the body and maintain a healthy balance of water, salts, and minerals such
as sodium, calcium, phosphorus, and in the blood.
NORMAL KIDNEY FUNCTION
The kidneys filter wastes from the blood and help balance water, salt, and mineral levels in the blood. To
do this, blood from the body enters the kidney. Inside the kidney, blood is filtered, and waste is removed.
Salt, water, and minerals are added if needed. The filtered blood is returned to the body and the waste
from the blood is sent to the bladder as urine. The kidneys also produce three important hormones: renin,
erythropoietin, and the active form of vitamin D. Renin helps regulate blood pressure. Erythropoietin is
needed to make red blood cells. The body needs the active form of vitamin D ( 1,25-dihydroxyvitamin
D) to absorb calcium from food. Together, vitamin D and calcium help build healthy bones and maintain
normal muscle function. Blood flow to the kidneys is very important for the kidneys to work well. If
blood flows to a kidney gets blocked, part or all of that kidney may die. This can lead to kidney failure.
CHRONIC KIDNEY DISEASE
Chronic Kidney
Disease is an
umbrella term that
describes kidney
damage or a
decrease in the
glomerular
filtration rate
(GFR) lasting for
three or more
months. CKD is
associated with
decreased quality
of life, increased
healthcare
expenditures, and
premature death. Untreated CKD can result in end-stage kidney disease (ESKD), formerly known as end-
stage renal disease (ESRD), which is the final stage of CKD. ESKD results in retention of uremic waste
products and the need for renal replacement therapy (RRT), such as dialysis or kidney transplantation
(Chicca, 2020). Risk factors include cardiovascular disease, diabetes, hypertension, and obesity.
Pathophysiology
In the early stages of CKD, there can be significant damage to the kidneys without signs or symptoms.
The pathophysiology of CKD is not yet clearly understood, but the damage of the kidneys is thought to be
caused by prolonged acute inflammation that is not organ specific and thus has subtle systemic
manifestation.
Stages of Chronic Kidney Disease
CKD often progresses over time and has 5 stages depending on how well your kidneys are currently able
to filter your blood. Your glomerular filtration rate (GFR) indicates how well your kidneys are working.
Stage 1 of CKD, the kidneys are damaged, but are almost able to function normally GFR above 90
mL/min/1.73m2. Stage 2 of CKD, damage has caused a mild loss of your kidney function GFR 60-89
mL/min/1.73m2. Stage 3 of CKD, the damage has caused a moderate loss of your kidney function GFR:
30-59 mL/min. Stage 4 of CKD, Description: damage has caused a severe loss of your kidney function
GFR: 15-29 mL/min. Stage 5 of CKD, the kidneys have failed GFR less than 15.
Clinical Manifestations
Elevated serum creatinine levels indicate underlying kidney disease as the creatinine level increases,
symptoms of CKD begin. Those with CKD are one of the most symptomatic groups among patients with
chronic disease. Fluid retention, evidenced by both edema and congestive heart failure, develops. As the
disease progresses, abnormalities in electrolytes occurs, heart failure worsens, and hypertension becomes
more difficult to control, often due to fluid volume excess.
Assessment and Diagnostic Findings
The Glomerular Filtration Rate (GFR) is the amount of plasma filtered through the glomeruli per unit of
time. Creatinine clearance is a measure of the amount of creatinine the kidney is able to clear in a 24-hour
period. The normal value of creatinine for male is 0.7 to 1.3 mg/dL or 61.9 to 114.9 µmol/L, and for
female is 0.6 to 1.1 mg/dL (53 to 97.2 µmol/L.
Medical Management
The management of a patient with CKD includes treatment of underlying causes. Regular clinical and
laboratory assessment is important to keep the blood pressure below 125 to 130/80 mmHg. In this case,
the patient was admitted and prescribed with pharmacologic treatment including Folart 1 tab OD,
Furosemide 40 mg q6, Erythropoiet in 4000 units STAT, Clopidogrel 75 mg/tab OD, Atorvastatin
40mg/tab OD, Amlodipine 5mg/tab, Clonidine 75mg/tab BID, TMZ MR 35mg,tab BID, Cardipres
12.5mg/tab, Renalog/tab TID, NaCI/tab TID.
