Cases Flashcards
(7 cards)
49-year-old man presents with a 6-month history of bloating and loose stools. He
has 4 to 7 bowel movements daily (baseline, 1-2 daily), with nocturnal stools. His
bloating is relieved after a bowel movement. There has been no hematochezia or
melena. He underwent a Roux-en-Y gastric bypass, 3 years earlier, for medically
complicated obesity and has lost 54.5 kg since the operation. Although his weight
loss has stabilized, he has lost an additional 4.5 kg during the last month. He takes an
iron-containing multivitamin and oral vitamin B12 daily. Findings on examination are
unremarkable. His Stool cultures, including repeated cultures for ova and parasites,
were negative and tissue transglutaminase IgA was normal. Findings on colonoscopy
with random biopsies were normal. Esophagogastroduodenoscopy revealed post-
Roux-en-Y anatomy, with otherwise normal findings.
A) What is the most probable diagnosis and how to confirm?
B) What is the most suitable treatment?
SIBO
46 year old man with a 10-year history of type 2 diabetes presents with a 6-week
history of bilateral leg swelling. He reports that he had been taking non-steroidal
anti-inflammatory drugs (NSAIDs) for osteoarthritis regularly for the past 3 months.
Investigations reveal: eGFR > 60 mL/min/ 1.73 m2; urinalysis: protein 4 +, blood negative;
protein : creatinine ratio 1680 mg/mmol; and a serum albumin of 14 g/L. Serum albumin and
urinary albumin : creatinine ratios 4 months previously were 36 g/L and 25 mg/mmol,
respectively. What is the most likely diagnosis and Justify?
A. Amyloidosis
B. Diabetic nephropathy
C. IgA nephropathy
D. Minimal change disease
E. Tubulointerstitial nephritis
B
A 69 year old man is diagnosed with streptococcal endocarditis and commenced on
benzylpenicillin and gentamicin. His renal function is normal on admission, but 1 week
later it has deteriorated (eGFR 28 mL/min/1.73 m2). Investigations reveal: urinalysis:
blood 3+, protein 3 +; ultrasound scan: normal-sized kidneys with no hydronephrosis;
serum complement level (C3 and C4) is low.
A) What is the most likely diagnosis?
Infective endocarditis-associated glomerulonephritis (IE-GN)
B) How can you manage this patient
1-Continue appropriate antibiotic therapy:
2-Nephrology referral:
A 59-year-old man with rheumatoid arthritis presents with chronic diarrhea. The symptoms
first began 18 months ago and have been progressively worse over time. He describes his bowel
movements as nonbloody, “flaky,” and “like oatmeal.” He reports early satiety and meal-related
nausea and bloating. He has lost 20 pounds unintentionally over the past year.
Review of systems reveals lower extremity swelling, orthopnea, dyspnea on exertion, and
fatigue. He complains of progressive abdominal swelling. In addition, he reports tingling in his
bilateral hands and legs in a “stocking and glove” distribution.
On physical exam, he is found to have orthostatic vital signs. There is an S3 gallop. His
liver is enlarged, and there is evidence of ascites. There are no spider angiomata, no pal-
mar erythema, and no asterixis. Neurological exam reveals evidence of peripheral sen-
sory and motor neuropathy. Relevant laboratories include AST = 84; ALT = 66; ALP = 249;
albumin = 2.1; serum carotene = 8.
▶ What is the most likely diagnosis?
Amyloidosis
▶ How can you confirm the diagnosis?
Biopsy with Congo red staining:
Best initial test is abdominal fat pad aspiration or biopsy of affected organ (e.g., rectal, small bowel, liver).
Under polarized light, apple-green birefringence confirms amyloid.
2. Typing of amyloid protein:
After biopsy, use immunohistochemistry or mass spectrometry to distinguish AL (light chain) vs AA (serum amyloid A protein).
3. Serum and urine protein electrophoresis with immunofixation (SPEP/UPEP):
Diarrhea + Dysmotility + Heart failure + Neuropathy
Amyloid
Diarrhea + “congophilic angiopathy.”
Amyloidosis
Diarrhea + dysmotility + heart failure + orthostatic hypotension.
Amyloidosis
