A 5-day-old male newborn is brought to the physician by his mother because of yellowish discoloration of the skin for 1 day. The discoloration first appeared on his face and then spread to his trunk. There have been no changes in his bowel habits or urination. He was born at 38 weeks' gestation via uncomplicated vaginal delivery. He is exclusively breastfed every 2–3 hours. Examination shows scleral icterus and jaundice of the face, chest, and abdomen. Laboratory studies show: Hemoglobin 17.6 g/dL Reticulocytes 0.3% Maternal blood group A, Rh-negative Fetal blood group 0, Rh-positive Serum Bilirubin, total 7 mg/dL Direct 0.6 mg/dL Free T4 12 μg/dL Which of the following is the most likely diagnosis?

Physiological neonatal jaundice

A 3-week-old newborn male is brought to the physician because of increasing yellowing of his eyes and skin for 2 weeks. The mother has noticed that his stools have been paler than usual for the past week. He is exclusively formula fed, and feeds every 4 hours with a strong sucking reflex. The patient was delivered vaginally at 39 weeks' gestation to a healthy woman without any complications. Vital signs are within normal limits. He is at the 50th percentile for length and at the 65th percentile for weight. Examination shows scleral icterus and jaundice. Abdominal examination reveals a palpable liver 2 cm below the right costal margin without splenomegaly. Serum studies show: Bilirubin Total 17 mg/dL Direct 13.3 mg/dL Alkaline phosphatase 1700 U/L AST 53 U/L ALT 45 U/L γ-Glutamyl transferase 174 U/L Blood group B positive This patient is at increased risk of developing which of the following?

Dark pigmentation on liver biopsy

A 28-year-old woman comes to the emergency department for a 1-week history of jaundice and nausea. She recalls eating some seafood last weekend at a cookout. She lives at home with her 2-year-old son who attends a daycare center. The child's immunizations are up-to-date, and his last hepatitis A vaccine was administered 6 weeks ago. The woman's temperature is 37.5°C (99.5°F), pulse is 82/min, and blood pressure is 134/84 mm Hg. Examination shows scleral icterus. The liver is palpated 2-cm below the right costal margin and is tender. Her serum studies show: Total bilirubin 3.4 mg/dL Alkaline phosphatase 89 U/L AST 185 U/L ALT 723 U/L Hepatitis A IgM antibody positive Hepatitis B surface antibody positive Hepatitis B surface antigen negative Hepatitis B core IgM antibody negative Hepatitis C antibody negative Which of the following health maintenance recommendations is most appropriate for the child at this time?

Administer hepatitis B immunoglobulin and hepatitis B vaccine

Administer hepatitis B immunoglobulin only

Administer hepatitis A vaccine and hepatitis A immunoglobulin

A 31-year-old man presents with jaundice, scleral icterus, dark urine, and pruritus. He also says that he has been experiencing abdominal pain shortly after eating. He says that symptoms started a week ago and have not improved. The patient denies any associated fever or recent weight-loss. He is afebrile and vital signs are within normal limits. On physical examination, the patient’s skin appears yellowish. Scleral icterus is present. Remainder of physical examination is unremarkable. Laboratory findings are significant for: Conjugated bilirubin 5.1 mg/dL Total bilirubin 6.0 mg/dL AST 24 U/L ALT 22 U/L Alkaline phosphatase 662 U/L A contrast CT of the abdomen is unremarkable. An ultrasound of the right upper quadrant reveals a normal gallbladder, but the common bile duct is not visible. Which of the following is the next best step in the management of this patient?

Endoscopic retrograde cholangiopancreatography (ERCP)

Serologies for antimitochondrial antibodies

Antibiotics and admit to observation

A 45-year-old woman comes to the emergency department complaining of abdominal pain for the past day. The pain is situated in the right upper quadrant, colicky, 8/10, and radiates to the tip of the right shoulder with no aggravating or relieving factors. The pain is associated with nausea but no vomiting. She tried to take over-the-counter antacids which relieved her pain to a certain extent, but not entirely. She does not smoke cigarettes or drink alcohol. She has no past medical illness. Her father died of pancreatic cancer at the age of 75, and her mother has diabetes controlled with medications. Temperature is 38°C (100.4°F), blood pressure is 125/89 mm Hg, pulse is 104/min, respiratory rate is 20/min, and BMI is 29 kg/m2. On abdominal examination, her abdomen is tender to shallow and deep palpation of the right upper quadrant. Laboratory test Complete blood count Hemoglobin 13 g/dL WBC 15,500/mm3 Platelets 145,000/mm3 Basic metabolic panel Serum Na+ 137 mEq/L Serum K+ 3.6 mEq/L Serum Cl- 95 mEq/L Serum HCO3- 25 mEq/L BUN 10 mg/dL Serum creatinine 0.8 mg/dL Liver function test Total bilirubin 1.3 mg/dL AST 52 U/L ALT 60 U/L Ultrasonography of the abdomen shows normal findings. What is the best next step in management of this patient?

Reassurance and close follow up

A 66-year-old man comes to the physician because of yellowish discoloration of his eyes and skin, abdominal discomfort, and generalized fatigue for the past 2 weeks. He has had dark urine and pale stools during this period. He has had a 10-kg (22-lb) weight loss since his last visit 6 months ago. He has hypertension. He has smoked one pack of cigarettes daily for 34 years. He drinks three to four beers over the weekends. His only medication is amlodipine. His temperature is 37.3°C (99.1°F), pulse is 89/min, respirations are 14/min, and blood pressure is 114/74 mm Hg. Examination shows jaundice of the sclera and skin and excoriation marks on his trunk and extremities. The lungs are clear to auscultation. The abdomen is soft and nontender. The remainder of the examination shows no abnormalities. Laboratory studies show: Hemoglobin 12 g/dL Leukocyte count 5,000/mm3 Platelet count 400,000/mm3 Serum Urea nitrogen 28 mg/dL Creatinine 1.2 mg/dL Bilirubin Total 7.0 mg/dL Direct 5.5 mg/dL Alkaline phosphatase 615 U/L Aspartate aminotransferase (AST, GOT) 170 U/L Alanine aminotransferase (ALT, GPT) 310 U/L γ-Glutamyltransferase (GGT) 592 U/L (N = 5–50 U/L) An ultrasound shows extrahepatic biliary dilation. A CT scan of the abdomen shows a 2.5-cm (1-in) mass in the head of the pancreas with no abdominal lymphadenopathy. The patient undergoes biliary stenting. Which of the following is the most appropriate next step in the management of this patient?

Gemcitabine and 5-fluorouracil therapy

A 50-year-old man is brought to the emergency department because of a 3-day history of left flank pain. The patient has had two episodes of urolithiasis during the last year. He initially had pain with urination that improved with oxycodone. Over the past day, the pain has worsened and he has additionally developed fever and chills. He has hypertension and type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for 20 years. He does not drink alcohol. His current medications include metformin and lisinopril. The patient appears ill and uncomfortable. His temperature is 39.1°C (102.3°F), pulse is 108/min, respirations are 22/min, and blood pressure is 90/62 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no murmurs, rubs, or gallops. Examination of the back shows left costovertebral angle tenderness. Physical and neurologic examinations show no other abnormalities. Laboratory studies show: Hemoglobin 14.2 g/dL Leukocyte count 13,900/mm3 Hemoglobin A1c 8.2% Serum Na+ 138 mEq/L K+ 3.8 mEq/L Cl- 98 mEq/L Calcium 9.3 mg/dL Glucose 190 mg/dL Creatinine 2.1 mg/dL Urine pH 8.3 Urine microscopy Bacteria moderate RBC 6–10/hpf WBC 10–15/hpf WBC casts numerous Ultrasound shows enlargement of the left kidney with a dilated pelvis and echogenic debris. CT scan shows a 16-mm stone at the left ureteropelvic junction, dilation of the collecting system, thickening of the wall of the renal pelvis, and signs of perirenal inflammation. Intravenous fluid resuscitation and intravenous ampicillin, gentamicin, and morphine are begun. Which of the following is the most appropriate next step in the management of this patient?

Ureteroscopy and stent placement

Biliary atresia and Kasai procedure for USMLE Step 3: High-Yield Surgery Lessons

🚧 Pathophysiology - Bile Duct Blockade

A progressive, idiopathic, fibro-obliterative process that destroys the extrahepatic (and often intrahepatic) bile ducts during early infancy.
The exact cause is unknown, but potential triggers include perinatal viral infections (Reovirus, CMV), an abnormal immune response, or genetic predisposition.
Obstruction of bile flow leads to cholestasis, causing direct hepatocyte injury from retained toxic bile acids.
This triggers a cascade of inflammation, progressive fibrosis, and ultimately, biliary cirrhosis and end-stage liver disease if untreated.

⭐ The process is time-sensitive. Fibrosis progresses rapidly, making the liver unsuitable for a Kasai portoenterostomy if diagnosis is delayed past 90-120 days of life.

Biliary atresia: Lymphocytes and apoptotic bile duct cells

👶 Jaundice That Lingers

Presents in a previously healthy-appearing infant, typically between 2-8 weeks of age.

Persistent Jaundice: The cardinal sign. Jaundice develops or persists beyond the typical 2-3 weeks of physiologic jaundice.
Stool & Urine Changes:
- Acholic Stools: Progressively pale, clay-colored stools due to biliary obstruction.
- Dark Urine: Tea-colored from renal excretion of conjugated bilirubin.
Lab Hallmark: Conjugated (direct) hyperbilirubinemia (Direct Bili >1 mg/dL or >20% of total).
Physical Exam: Firm, progressive hepatomegaly.

Infant Stool Color Chart: Normal vs. Acholic Stools

⭐ Critical Pearl: Infants often appear well and gain weight initially, which can falsely reassure caregivers and delay the crucial diagnosis past the optimal window for the Kasai procedure.

🔬 Diagnosis - Catching the Culprit

Initial Labs:
- ↑ Direct (conjugated) bilirubin is the hallmark.
- ↑ Gamma-glutamyl transpeptidase ($GGT$) is highly characteristic.
- ↑ AST/ALT.
Imaging Pathway:
- 1st Line (Ultrasound): Screens for other causes. May show absent/small gallbladder or the "triangular cord sign" (fibrous remnant of extrahepatic duct).
- 2nd Line (HIDA Scan): Hepatobiliary scintigraphy. After 5 days of phenobarbital pre-treatment to stimulate bile flow, shows hepatic uptake but no excretion of tracer into the small bowel.
- Gold Standard (Intraoperative Cholangiogram): Definitive diagnosis. Dye is injected directly into the gallbladder/biliary tree during surgery, confirming blockage before proceeding with Kasai.

⭐ Failure of radiotracer to appear in the intestine on a HIDA scan, even after phenobarbital stimulation, is the most reliable non-invasive finding pointing to biliary atresia over other causes of neonatal cholestasis.

🔪 The Kasai Fix: Hepatoportoenterostomy

Procedure: A hepatoportoenterostomy (Roux-en-Y anastomosis).
- The fibrotic, atretic extrahepatic biliary tree is excised.
- A loop of jejunum is anastomosed to the liver capsule at the porta hepatis.
- This allows bile to drain directly from microscopic intrahepatic ductules into the small intestine.
Timing is Critical:
- Best outcomes if performed before 60 days of age.
- Success rates decline sharply after 90 days due to irreversible cirrhosis.

⭐ The Kasai procedure is palliative, not curative. It aims to restore bile flow to delay the need for liver transplantation. Many patients ultimately require a transplant.

Post-op Management:
- Prophylactic antibiotics (e.g., trimethoprim-sulfamethoxazole) to prevent ascending cholangitis.
- Supplementation: Fat-soluble vitamins (A, D, E, K) and medium-chain triglycerides (MCTs).

⚡ Biggest Takeaways

Presents in neonates (2-8 weeks) with jaundice, dark urine, and pale/acholic stools.

Key lab finding is conjugated (direct) hyperbilirubinemia.

Pathophysiology: Progressive inflammatory obliteration of extrahepatic bile ducts.

Gold standard diagnosis is intraoperative cholangiogram.

Treatment is the Kasai procedure (hepatoportoenterostomy), best performed <60 days of age.

Despite surgery, most patients develop cholangitis and eventually need a liver transplant.

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