Harold Myers,a 58 year-old male, visited his internist with complaints of two months of progressive cough, hemoptysis, dyspnea, and confusion. He said that for years he had a chronic "smoker's cough" that was worse in the morning. During the last two months, however, his coughing progressed; Harold stated that he went into "coughing fits" that often made catching his breath difficult. He also noticed that his sputum was occasionally blood-tinged. Harold had become so short of breath recently that he got winded easily even when he cooked in the kitchen. These symptoms represented a dramatic change; Harold had been an active golfer for years and until two months ago he prided himself on still being able to walk an entire 18 holes. He also complained of some mild confusion. For example, he occasionally got lost while driving his usual route to work.

Past Medical History:Significant for a hospitalization for Pneumococcal Pneumonia two years ago.

Habits:He had a 60 pack-year smoking history. (Pack-years are defined as the number of packs per day the person smokes multiplied by the number of years the person has smoked; Mr. Myers began smoking one and a half packs per day at the age of 18.)

Medications:Albuterol inhaler for occasional wheezing

Physical Exam was remarkable for the following:Weight: 150 pounds, down from 170 pounds one year ago.Height:5 feet 11 inches.Temperature: 98.6. Pulse: 88. Respirations: 24. Blood Pressure: 140/88.Skin: Revealed a slightly bluish hue to his lips, nailbeds, and ears.Lungs: Revealed decreased breath sounds over the apex of the right lung.Lymph Nodes: No lymphadenopathy.Neurological Exam: He was alert and oriented to person, place, and time. Testing for long-term memory revealed that he could not remember his birthday nor his wife's birthday. His cranial nerves were intact. He had no sensory, motor, or cerebellar findings.

Laboratory Data:Serum electrolytes test revealed a sodium of 120 mEq/dl; the other electrolytes were normalHematocrit: 58 percent White blood cell count: 8,000 white cells with 60 percent neutrophils, 32 percent lymphocytes, 5 percent monocytes, 2 percent eosinophils, and 1 percent basophils

Urolithiasis

Case Scenario

Elijah, a forty-two year old history teacher, was in his office preparing notes for an upcoming seminar  when he was struck with a very sudden and intense pain in his side and lower back. He remained at his desk, breathing deeply, and the pain began to recede. Five minutes later, the pain was not as severe but Elijah was still uncomfortable and decided to call his physician. Elijah described his symptoms to the doctor’s receptionist and made an early afternoon appointment. One of Elijah’s colleagues drove Elijah to the doctor’s office. While on the way to his appointment, Elijah experienced another bout of severe pain and began to feel nauseous. The pain seemed to be spreading into his lower abdomen and groin.After asking Elijah a few questions about his symptoms, the doctor requested an abdominal x-ray, several blood tests, and urinalysis. As Elijah supplied the urine sample he was disturbed to notice that the urine had a pinkish cast. The physician returned and informed Elijah that he had a kidney stone which, based on its size, should pass on its own within a day or so. The doctor told Elijah that he should rest at home until the stone passed, drink at least 2-3 quarts of water each day, and strain his urine in order to retrieve the stone for analysis. The doctor also gave Elijah a prescription for pain medication.Elijah passed the stone the following morning and brought it to the doctor’s office. Analysis of the stone’s composition revealed that it was a calcium stone. Elijah’s blood and urine tests had also shown high calcium levels. Based on this, the doctor told Elijah to eat fewer foods containing calcium or oxalate and provided Elijah with a lists of foods to limit. He also told Elijah to continue to drink at least two quarts of water each day.

Case Description

The presence of kidney stone, or urinary caliculi, in the urinary tract is called urolithiasis. These stones form from materials that are excreted by the kidneys. Normally these excreted materials stay dissolved in urine, but in some individuals they form precipitates that can develop into kidney stones. Kidney stones can form from several different substances. Kidney stone analysis, blood tests, and urinalysis all assist a physician in determining how best to avoid the development of future stones. Calcium stones are most common, comprising between 80 and 90 percent of urinary caliculi. The calcium stones are formed from calcium phosphate or calcium oxalate, and persons predisposed to developing these stones are often instructed to decrease calcium and oxalate intake. In some cases, medications are prescribed that decrease calcium excretion by the kidneys or alter urine pH, a factor in kidney stone formation.The pain associated with the blockage of the urinary tract by a kidney stone is called renal colic and can be very intense. Treatment depends primarily on the size of the stone. Stones smaller than 5 mm are usually passed without assistance, and passage is facilitated by drinking plenty of water. Larger stones can be pulverized with shockwaves or surgically removed depending on the size and the location of the stone. Sometimes, a stone within a ureter is removed by inserting a fiberoptic device through the urethra and ureter and either grabbing or destroying the stone.

Questions

1. List the components of the urinary tract from the renal pelvis outward.

Renal pelvis, ureter, urinary bladder, urethra

2. Why would water facilitate the passage of kidney stones?

The water would flush the stone through the urinary tract.

3. Why would water aid in the prevention of developing future kidney stones?

 Increased intake of water would dilute the urine, thereby decreasing the concentration of stone forming substances and decreasing the likelihood that stones will form.

4. List the three stages in the formation of urine and describe each stage with regard to the structures involved and the direction substance transport.

1.Glumelular Filtration - Movement of substances from the glomerular capillaries into the renal tubule.2. Tubular reabsorption - Movement of Substances from the renal tubule into the peritubular capillaries3. Tubular secretion -Movement of substances from the peritubular capillaries into the renal tubule.

5. The glomerular filtrate concentration of calcium (Ca+2) is about 4 mEq/L. The concentration of calcium in the urine is about 5 mEq/L. How would you explain this difference?

Additional calcium is moved from the plasma in the peritubular capillaries to the fluid in the renal tubule during tubular secretion.