Yes. The liver is the only organ in the human body capable of reconstituting up to 75% of its tissues. Man has known this impressive ability since antiquity. Greek mythology tells that the titan Prometheus was condemned by Zeus, the supreme god, to spend eternity chained to a rock, suffering the attack of a vulture that devoured pieces of his liver from time to time. The punishment would be infinite precisely because of the regeneration of the organ. Despite being very creative, the story sounds a little absurd if we focus on the medical aspects. After centuries of experiments, experts have discovered that the liver cannot repair itself several times – and even when a piece of the organ is donated only once, the “rebirth” can have some problems. “When we remove part of the liver, the blood vessels do not fully recover and circulation is compromised”, says surgeon Tércio Genzini, from the Beneficência Portuguesa hospital, in São Paulo, and an expert on the subject. Another problem is that the regenerated tissue is usually fibrous, harder than the original. This increases the chances of the donor having liver cirrhosis, a disease that can cause the organ to stop working, leading to death. In any case, liver transplantation is the typical case in which the benefits outweigh the possible problems. “When we remove part of the organ from a living donor and transfer it to the recipient, the organ multiplies in both patients. In both, tissue reconstitution is complete, and the risk of life for the donor is only 1%”, says Tércio. Called intervivo transplantation, this type of operation is completing 50 years of history – in 1954, a patient received a new kidney in the pioneering intervivo transplantation in Boston, in the United States. According to the Brazilian Association of Organ Transplantation, 24% of transplants performed in the first half of this year in Brazil were of this type. In the illustration on the side, we give more details of the four main organs or tissues that can be transplanted between two living people: the liver, the kidney, the marrow and the blood. In addition, part of the lung and pancreas can be used for donations by living people, but these transplant modalities are much rarer in the country.
– Can you live without a stomach?
– How many days can a chicken live without a head?
operation game We have gathered the main body parts that can be transplanted between living people
LIVER
TRANSPLANTS IN 2004*: 432
PERCENTAGE WITH LIVING DONORS: 18%
RISK OF REJECTION: 10%
WAITING LIST: 5,587 patients
ORGAN SURVIVAL: 12 hours outside the body
The liver is the only transplantable organ that regenerates. The possibility of having an intervival transplant drastically reduced mortality on the waiting list. Children were the main beneficiaries: this technique represents more than 50% of pediatric transplants. In 2003, the liver occupied second place in the ranking of organ transplants, with 792 operations. In front of him, only the kidneys
MARROW
TRANSPLANTS IN 2004*: 510
PERCENTAGE WITH LIVING DONORS: 100% (52% with other people’s cells and 48% with the individual’s own cells)
RISK OF REJECTION: Very rare (with cells from the individual) or less than 10% (with cells from another person)
WAITING LIST: There is no unified registration. Time varies depending on the hospital
TISSUE SURVIVAL: 10 years (cells frozen in liquid nitrogen)
The marrow, a structure that is inside the bone and produces the components of blood, is the only tissue that can be transplanted with cells from the person himself — in general, cancer patients. Doctors take the marrow or blood cells to put them back in after chemotherapy. But the recurrence of the disease is lower in transplants with cells from another donor
BLOOD
TRANSFUSIONS IN 2004**: 309 thousand
PERCENTAGE WITH LIVING DONORS: 100%
RISK OF REJECTION: 1%
WAITING LIST: None
TISSUE SURVIVAL: 35 days outside the body (stored at 4°C)
A transfusion is a transplant of liquid tissue, but nobody talks about a “blood transplant”, probably because this procedure predates other techniques – it appeared in the 19th century, and doctors preferred to keep the name “transfusion”. Rigorous testing of donors and materials greatly reduced the transmission of contagious diseases. In the United States, there is one case of AIDS infection for every 500 transfusions
KIDNEY
TRANSPLANTS IN 2004*: 1,609
PERCENTAGE WITH LIVING DONORS: 46%
RISK OF REJECTION: 20%
WAITING LIST: 30,423 patients
ORGAN SURVIVAL: 36 hours outside the body
The first kidney transplant was performed in 1954 between two living twin brothers to decrease the likelihood of rejection. The kidney is the most common organ in live-in transplants, as there is not much difficulty for the donor to survive with only one of the organs
* In Brazil, during the first half of this year.
Source: Brazilian Association of Organ Transplants (ABTO)
** Transfusions in the unified health system (SUS) in the first half of this year.
Source: Ministry of Health