Transplant Surgery

Transplant Surgery Indian Medical PG Question 1: Acute graft rejection occurs within?

• A. Few minutes
• B. 6-12 months
• C. Few hours
• D. < 6 months (Correct Answer)

Transplant Surgery Explanation: ***< 6 months*** - **Acute graft rejection** typically occurs within the first few **weeks to months** after transplantation due to a T-cell mediated immune response against the donor organ [1]. - While it can manifest at any time, the majority of cases occur within the **first 6 months** post-transplant, making this the most appropriate time frame [1]. *Few minutes* - Rejection presenting within minutes of transplantation is characteristic of **hyperacute rejection**, which is caused by pre-existing **donor-specific antibodies** [1]. - This rapid form of rejection is mediated by **complement activation** and leads to immediate graft failure [1]. *6-12 months* - Rejection occurring in this timeframe might still be acute, but the peak incidence is generally earlier. - Rejection presenting after 6 months is often categorized as **late acute rejection** or may start to transition towards signs of chronic rejection, which occurs over a longer period. *Few hours* - Rejection within a few hours could be a very early form of **acute rejection** or a delayed presentation of **hyperacute rejection** [1]. - However, the classic presentation of acute rejection is more prolonged than a few hours, usually developing over days to weeks. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 241-242.

Transplant Surgery Indian Medical PG Question 2: What is the documented mortality rate for healthy liver donors undergoing donor hepatectomy?

• A. Mortality for donor is 0.6 to 0.8 %
• B. Mortality for donor is 0.5 %
• C. Mortality for donor is 0.2 to 0.4 % (Correct Answer)
• D. Mortality for donor is 1%

Transplant Surgery Explanation: ***Correct: Mortality for donor is 0.2 to 0.4%*** - Studies indicate that the **mortality rate** for healthy liver donors undergoing **donor hepatectomy** is very low, typically ranging from **0.2% to 0.4%**. - This rate reflects the extensive **pre-operative screening** and careful surgical techniques used to ensure donor safety. - Current data from major transplant centers worldwide support this range as the most accurate representation of donor risk. *Incorrect: Mortality for donor is 0.6 to 0.8%* - This range is **higher** than the generally accepted and documented mortality rates for healthy liver donors. - While complications can occur, fatal outcomes are rare, making this percentage an **overestimation** of actual risk. *Incorrect: Mortality for donor is 0.5%* - This mortality rate is also **higher** than the current reported rates for living liver donation in well-established centers. - Continuous advancements in surgical safety and donor selection have driven the mortality rate **below 0.5%** in most high-volume centers. *Incorrect: Mortality for donor is 1%* - A 1% mortality rate for healthy liver donors would be considered **unacceptably high** given the current standards of care. - This percentage severely **overestimates** the actual risks associated with living related liver donation and does not reflect modern surgical outcomes.

Transplant Surgery Indian Medical PG Question 3: Most common malignancy in post-transplant individuals:

• A. Kaposi sarcoma
• B. PTLD
• C. CNS lymphoma
• D. Squamous cell carcinoma of skin (Correct Answer)

Transplant Surgery Explanation: Most common malignancy in post-transplant individuals: ***Squamous cell carcinoma of skin*** - **Squamous cell carcinoma (SCC) of the skin** is the most common malignancy in post-transplant individuals, largely due to **immunosuppression** which impairs immune surveillance against oncogenic viruses and sunlight-induced mutations [1]. - The risk of SCC is significantly increased (up to 65-fold) in transplant recipients, often presenting as **multiple tumors** and exhibiting a more aggressive course than in the general population [2]. *Kaposi sarcoma* - **Kaposi sarcoma (KS)** is associated with **human herpesvirus 8 (HHV-8)** infection and is more common in transplant recipients compared to the general population, but it is not the *most common* malignancy [1]. - While its incidence is increased, it remains less frequent than skin cancers like SCC. *PTLD* - **Post-transplant lymphoproliferative disorder (PTLD)** is a significant complication of organ transplantation, primarily driven by **Epstein-Barr virus (EBV)** infection in the setting of immunosuppression [1]. - PTLD is a serious malignancy, but its overall incidence is less than that of skin cancers. *CNS lymphoma* - **CNS lymphoma** can occur in post-transplant patients, often linked to **EBV infection** and immunosuppression [1]. - Although it is a severe complication, its incidence is considerably lower than that of skin cancers in this population.

Transplant Surgery Indian Medical PG Question 4: A 23-year-old female underwent kidney transplantation and developed acute humoral rejection after 8 days, which was successfully managed with tacrolimus and another drug that suppresses both B and T lymphocytes. What is the drug that targets both B and T lymphocytes by inhibiting de novo synthesis of purines?

• A. Prednisone
• B. Methotrexate
• C. Mycophenolate mofetil (Correct Answer)
• D. Cyclophosphamide

Transplant Surgery Explanation: ***Mycophenolate mofetil*** - This drug inhibits **inosine monophosphate dehydrogenase**, an enzyme crucial for the **de novo synthesis of guanine nucleotides** in lymphocytes. - This selective inhibition effectively suppresses the proliferation and function of both **B and T lymphocytes**, making it a cornerstone in preventing transplant rejection. *Methotrexate* - **Methotrexate** is an **antimetabolite** that primarily inhibits **dihydrofolate reductase**, interfering with DNA synthesis and cell proliferation. - While it has immunosuppressive effects, its primary mechanism in inhibiting purine synthesis is not de novo synthesis in the same manner as mycophenolate mofetil. *Prednisone* - **Prednisone** is a **corticosteroid** that exerts its immunosuppressive effects through broad anti-inflammatory actions, genomic and non-genomic effects, affecting the function of various immune cells. - It does not specifically target **de novo purine synthesis** as its primary mechanism of immunosuppression. *Cyclophosphamide* - **Cyclophosphamide** is an **alkylating agent** that cross-links DNA strands, leading to cell cycle arrest and apoptosis, particularly in rapidly dividing cells like lymphocytes. - While it is a potent immunosuppressant affecting both B and T cells, its mechanism does not involve the inhibition of **de novo purine synthesis**.

Transplant Surgery Indian Medical PG Question 5: What is the consequence of preformed antibodies in organ transplantation?

• A. Delayed T-cell mediated rejection
• B. Long-term graft dysfunction due to chronic inflammation
• C. Post-transplant antibody-mediated rejection
• D. Immediate graft failure due to preformed antibodies (Correct Answer)

Transplant Surgery Explanation: ***Hyperacute rejection*** - This occurs immediately after transplant due to **preformed antibodies** reacting against donor antigens, leading to rapid allograft failure [1]. - It is typically associated with **complement activation** and often results in thrombosis of the graft vessels [1]. *Acute rejection* - Primarily mediated by **T cells** rather than preformed antibodies, occurring days to months after transplantation [2]. - Involves a **cellular immune response**, unlike hyperacute rejection which is antibody-mediated [2]. *Acute humoral rejection* - Also involves antibodies but develops **days to weeks** post-transplant rather than immediately like hyperacute rejection. - This type is characterized by a **specific antibody response** and complement activation, but is not due to preformed antibodies. *Chronic rejection* - A long-term process that develops over months to years due to **persistent immune-mediated injury** to the graft, leading to gradual loss of function. - Involves mechanisms such as **tissue fibrosis and vascular changes**, differing from the immediate action of preformed antibodies in hyperacute rejection. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 241-242. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, p. 242.

Transplant Surgery Indian Medical PG Question 6: All of the following are absolute contraindications for renal transplantation except:

• A. Active infection
• B. Active malignancy
• C. Active drug abuse
• D. Reduced life expectancy (Correct Answer)

Transplant Surgery Explanation: ***Reduced life expectancy*** - While a significantly reduced life expectancy due to certain **comorbidities** may influence the decision to transplant, it is not an absolute, but rather a relative, contraindication, as individual cases vary. - Ethical considerations and the potential for improved quality of life may still support transplantation in some cases, even with a **limited prognosis**. *Active infection* - An **active systemic infection** is an absolute contraindication due to the high risk of severe complications, including sepsis and infection of the transplanted organ, especially with immunosuppression. - The patient must be free of active infection before transplantation to ensure the safety and success of the procedure. *Active malignancy* - The presence of an **active malignancy** is an absolute contraindication because immunosuppressive therapy post-transplant can accelerate cancer progression and metastasis. - Patients typically require a **disease-free interval** (e.g., 2-5 years) after cancer treatment before being considered for transplantation. *Active drug abuse* - **Active illicit drug abuse** is an absolute contraindication due to concerns about adherence to the complex post-transplant medical regimen, potential for infections, and overall poor health outcomes. - Successful transplantation requires strict adherence to medication schedules and follow-up, which is jeopardized by **active substance use**.

Transplant Surgery Indian Medical PG Question 7: A 45 year old underwent surgery for rectal prolapse. At present, he complains of sexual dysfunction which is probably due to the injury of:

• A. Pelvic autonomic nerves (Correct Answer)
• B. Urinary bladder
• C. Rectum
• D. Inferior mesenteric artery

Transplant Surgery Explanation: ***Pelvic autonomic nerves*** - Surgical procedures in the **pelvic region**, such as for rectal prolapse, carry a risk of damaging the **pelvic autonomic nerves**, which are crucial for sexual function. - Injury to these nerves can lead to various forms of **sexual dysfunction**, including erectile dysfunction in men, due to impaired nerve signaling to the genital organs. *Urinary bladder* - While the urinary bladder is anatomically close to the rectum, direct injury to the bladder itself during rectal prolapse surgery typically leads to **urinary symptoms** (e.g., incontinence, retention), not primarily sexual dysfunction. - Though bladder dysfunction can indirectly impact sexual activity, it's not the direct cause of primary sexual dysfunction following injury in this context. *Rectum* - The surgery is performed on the rectum, and while complications can occur, direct injury to the rectal wall itself primarily results in issues such as **fecal incontinence, bleeding, or infection**. - The rectum's primary role is in digestion and defecation, and its injury does not directly cause sexual dysfunction unrelated to nerve damage. *Inferior mesenteric artery* - The **inferior mesenteric artery (IMA)** supplies blood to the distal colon and rectum, and its injury during surgery would primarily lead to **ischemia or necrosis** of the supplied bowel segments. - While a severely compromised blood supply could have systemic effects, direct injury to the IMA is not a direct or common cause of sexual dysfunction.

Transplant Surgery Indian Medical PG Question 8: A 4-year-old child was brought to the hospital with right impalpable testis. During diagnostic laparoscopy for undescended testis, there are blind testicular vessels. What should be done next?

• A. Abdominal exploration
• B. Inguinal exploration
• C. Scrotal exploration
• D. Nothing is to be done (Correct Answer)

Transplant Surgery Explanation: ***Nothing is to be done*** - The presence of **blind-ending testicular vessels** on diagnostic laparoscopy is diagnostic of **vanishing testis syndrome** (testicular regression syndrome). - This finding indicates that the testis underwent **atrophy and resorption** during fetal development or early infancy, and **no viable testicular tissue remains**. - The blind vessels represent **remnant vascular structures** where the testis once existed, confirming absence of testicular tissue beyond that point. - **No further surgical exploration is required** as the laparoscopy has already provided definitive diagnosis - the testis is absent, not located elsewhere. - This completes the diagnostic and therapeutic management for this condition. *Inguinal exploration* - This would be indicated if the testicular vessels were seen **entering the internal inguinal ring**, suggesting an inguinal or high scrotal location. - With **blind-ending vessels**, the testis is confirmed absent, making inguinal exploration unnecessary and futile. - Inguinal exploration would find no testicular tissue and subject the child to unnecessary additional surgery. *Abdominal exploration* - This is not needed as **diagnostic laparoscopy has already visualized the abdomen** and identified blind vessels. - If vessels were patent and leading to an intra-abdominal testis, orchidopexy would be performed laparoscopically. - Blind vessels rule out intra-abdominal testis location. *Scrotal exploration* - This approach is only appropriate for **palpable undescended testes** in the superficial inguinal pouch or high scrotum. - The testis is **impalpable** and laparoscopy shows **no testicular tissue exists**, making scrotal exploration illogical and non-contributory.

Transplant Surgery Indian Medical PG Question 9: A patient arrived in ER following an accident with hypotension, respiratory distress and subcutaneous emphysema with no entry of air on one side. What will be the best management?

• A. Continue PPV
• B. Needle decompression in 5th intercostal space in the midaxillary line (Correct Answer)
• C. Shift to ICU and intubate
• D. Secure IV line and start fluid resuscitation after insertion of the wide-bore IV line

Transplant Surgery Explanation: ***Needle decompression in 5th intercostal space in the midaxillary line*** - This clinical presentation of hypotension, respiratory distress, and subcutaneous emphysema suggests a **tension pneumothorax**, which requires immediate decompression. - The 5th intercostal space in the midaxillary line is the recommended site for **needle decompression** as it is safer and more effective than the traditional 2nd intercostal space in the midclavicular line. *Continue PPV* - Continuing positive pressure ventilation (PPV) in a patient with a tension pneumothorax can worsen the condition by increasing intrathoracic pressure and exacerbating **hemodynamic collapse**. - PPV can force more air into the pleural space, further compressing the lung and mediastinal structures. *Shift to ICU and incubate* - While ICU admission and intubation might be necessary after initial stabilization, these steps are not the immediate management for a **life-threatening tension pneumothorax**. - Delaying decompression to perform these actions would be detrimental due to rapid clinical deterioration. *Secure IV line and start fluid resuscitation after insertion of the wide-bore IV line* - Fluid resuscitation is important for managing hypotension, but it's secondary to addressing the mechanical cause of hypotension in a tension pneumothorax. - Prioritizing fluid resuscitation over immediate decompression fails to address the underlying problem of **competing intrathoracic pressure**.

Transplant Surgery Indian Medical PG Question 10: A 60-year-old diabetic man is admitted to the hospital with a diagnosis of acute cholecystitis. The white blood cell count is 28,000, and a plain film of the abdomen and computed tomography scan show evidence of intramural gas in the gallbladder. What is the most likely diagnosis?

• A. Emphysematous gallbladder (Correct Answer)
• B. Acalculous cholecystitis
• C. Cholangiohepatitis
• D. Sclerosing cholangitis

Transplant Surgery Explanation: ***Emphysematous gallbladder*** - The presence of **intramural gas** in the gallbladder wall, along with signs of **acute cholecystitis** and a high WBC count in a diabetic patient, is highly characteristic of emphysematous cholecystitis. - This severe form of cholecystitis is caused by gas-forming organisms, often seen in older, diabetic, or immunocompromised patients. *Acalculous cholecystitis* - This condition is **acute inflammation of the gallbladder** without the presence of gallstones, often seen in critically ill patients. - While it can be severe, it does not typically present with **intramural gas** as a primary diagnostic feature unless complicated by gas-forming organisms, which would then lead to emphysematous cholecystitis. *Cholangiohepatitis* - This refers to inflammation of the **bile ducts and liver parenchyma**, often presenting with fever, jaundice, and RUQ pain, but less commonly with gallbladder wall thickening or intramural gas. - Diagnosis usually requires evidence of **intrahepatic or extrahepatic bile duct dilation** or stones, which are not described here. *Sclerosing cholangitis* - This is a chronic, progressive cholestatic liver disease characterized by **inflammation and fibrosis of the bile ducts**, leading to strictures. - It presents with symptoms like **pruritus, fatigue, and jaundice**, and a diagnosis is typically made by cholangiography showing "beading" of the bile ducts; it does not involve intramural gallbladder gas.

Transplant Surgery Flashcard 1 of 8

Question: _____ is the father of modern transplant surgery and performed the first human liver transplant.

Answer: Thomas Starzl

Transplant Surgery Flashcard 2 of 8

Question: The most common intestinal graft is _____ graft

Answer: small bowel

Transplant Surgery Flashcard 3 of 8

Question: Organ implanted in the same anatomic location in the recipient as it was in the donor is known as _____ transplantation

Answer: orthotoptic

Transplant Surgery Flashcard 4 of 8

Question: In a live donor, the renal artery is anastomosed end to _____ with the internal iliac artery

Answer: end

Transplant Surgery Flashcard 5 of 8

Question: Which kidney is taken during donor transplantation? Why? _____

Answer: Left

Transplant Surgery Flashcard 6 of 8

Question: In a deceased donor, the renal artery is anastomosed end to _____ with the external iliac artery or common iliac artery

Answer: side

Transplant Surgery Flashcard 7 of 8

Question: Auxillary orthoptic liver transplantation _____ be done in cases of irreversible liver failure

Answer: cannot (can/cannot)

Transplant Surgery Flashcard 8 of 8

Question: Compared to islet cell transplantation, there is a _____ chance of requiring insulin after whole-organ pancreas transplantation

Answer: lesser