CASE 1

Clinical History:

A 10-year-old caucasian girl was brought by her parents to their family physician. History revealed that the child had a sore throat for about 10 days prior to the office visit. Initial laboratory tests ordered by the family physician revealed an elevated BUN and creatinine. A urinalysis showed hematuria with dysmorphic RBC's. The patient is referred to a nephrologist. The nephrologist, based upon the usual course of this illness, elects to follow the patient. However, two weeks later, the C3 is still decreased.

Pathologic Findings:

A renal biopsy was performed next.

Image 1.1:

Image 1.2:

What are the light microscopic findings?

Image 1.3:

What does the immunofluorescence staining show in image 1.3 for C3 (staining was negative with C1q, IgM, and IgA)? Staining for IgG is +/-.

Image 1.4:

What does the electron microscopy show?

Questions:

1. What tests should be ordered?
2. What diagnosis is suggested at this point?
3. What is the differential diagnosis?
4. What additional laboratory tests should be ordered?

CASE 2

Clinical History:

A 25-year-old man works in a military fuel depot. He began having respiratory difficulty along with red-tinged sputum. Two months later, he had increasing malaise and flank pain. He went to see the base physician. The patient then developed very rapid onset of renal failure with hematuria within three days.

Pathologic Findings:

A renal biopsy was performed.

Image 2.1:

Image 2.2:

What does the light microscopy show?

Image 2.3:

What does the immunofluorescence show with staining for fibrinogen?

Image 2.4:

What does the immunofluorescence show with staining for IgG?

Questions:

1. What tests and procedures would you order?
2. What is the differential diagnosis?
3. What additional laboratory tests can be ordered?
4. What are issues to consider if the patient, despite therapy, developed chronic renal failure? Should relatives be pressured to become allograft donors? What are issues involved with hemodialysis?

CASE 3

Clinical History:

A young man in his early 20's had a routine checkup by his family physician, which included a urinalysis. The urinalysis revealed a few RBC's. Physical examination was non-contributory. A repeat urinalysis shows dysmorphic RBC's and RBC casts, but no WBC's.

Pathologic findings:

Though one diagnosis in particular is most strongly suspected and has no specific treatment, a renal biopsy was performed for confirmation of the diagnosis.

Image 3.1:

What does the light microscopy show?

Image 3.2:

What does the immunofluorescence show that represents the pattern seen with staining for both IgA and C3?

Image 3.3:

What does the urinalysis microscopic examination show?

Questions:

1. What additional history do you want to know?
2. What is the differential diagnosis?
3. What additional laboratory tests could be ordered?
4. What diagnosis would you consider if the patient had presented with petechiae and purpura of the skin?

CASE 4

Clinical History:

A 15-year-old girl seen by her family physician because of increasing lethargy. She had a recent history of the "flu". The child's condition does not improve after several weeks, so a renal biopsy is then done.

Pathologic Findings:

Image 4.1:

Image 4.2:

What does the light microscopy show (image 4.2 is stained with a trichrome stain)?

What diagnosis would you consider if the patient had been a 1 year old child with a history of failure to thrive and edema, urinalysis showing hyaline casts and oval fat bodies, proteinuria of 3.7 gm/day, and hypoalbuminemia with increased serum cholesterol?

Image 4.3:

What does the H&E appearance of the glomerulus show?

Image 4.4:

What is the essential feature seen in the electron micrograph?

Questions:

1. What additional history should be obtained?
2. What laboratory tests should be ordered?
3. What is the differential diagnosis?
4. What additional laboratory tests could be ordered?
5. What do you do next?

CASE 5

Clinical History:

A 41-year-old man is found to have proteinuria on urinalysis performed as part of a yearly checkup by his physician. The dipstick urinalysis showed no blood, glucose, or ketones. The microscopic urinalysis revealed only 1 RBC/hpf and no WBC/hpf. Physical examination findings include 1+ pitting edema of the lower extremities to the knees. His blood pressure is 130/80. The rectal examination reveals no masses, but the stool guaiac is positive. The lungs are clear to auscultation and percussion. Palpation of the abdomen reveals no masses, and bowel sounds are present. Additional laboratory testing revealed a 24 hour urine protein of 4.1 gm. His serum creatinine was 4.2 with BUN of 40. He was referred to a nephrologist, and a renal biopsy was performed.

Pathologic Findings:

Image 5.1:

Image 5.2:

What does the light microscopic appearance demonstrate (image 5.2 is a Jones silver stain) in all glomeruli?

Image 5.3:

What is the pattern seen on immunofluorescence with antibody to IgG?

Image 5.4:

What are the features demonstrated by electron microscopy?

Questions:

1. What is the differential diagnosis?
2. What additional laboratory testing would be useful?
3. What additional workup is necessary in this case?
4. What is the pathogenesis of the disease seen here?

CASE 6

Clinical History:

A 34-year-old man is found to have 1+ proteinuria on urinalysis performed as part of a pre-employment physical examination. The dipstick urinalysis showed no blood or ketones, but the glucose was 2+. Physical examination was unremarkable. His blood pressure was 135/85.

Image 6.1

Image 6.2

What light microscopic appearance is shown in images 6.1 and 6.2 (image 6.2 is a PAS stain) that was present in many glomeruli?

Questions:

1. What underlying disease process is suggested by these findings?
2. What additional laboratory testing would be helpful?
3. What other complications could be present, given his underlying disease?

Image 6.3:

Image 6.4:

4. How would you deal with the complication of hypertension?
5. In patients with this disease, without hypertension, what pharmacologic agent(s) would be helpful? Which should be avoided?
6. If the patient had undergone abdominal CT imaging with contrast, in order to investigate potential underlying conditions, and then developed acute renal failure, what issues would need to be addressed?