Introduction
Goodpasture’s syndrome, anti-glomerular basement membrane (GBM) disease/anti-GBM disease, is one of many severe but fortunately rare autoimmune diseases. In autoimmune diseases, the own body produces antibodies, i.e. actually “good defensive substances” of our body’s immune system, against the body’s own structures or cells. Normally, these antibodies are only formed after a person has come into contact with a substance that is foreign to the body, has recognized it as such thanks to its unknown surface structures and then activates the body’s own defense cells.
These are then specifically formed and imprinted on this one type of foreign substance and thus potential pathogens. They can therefore only recognize this type and are otherwise harmless, so they do not harm our body any further. But if it happens that the body suddenly or gradually no longer recognizes structures that are actually familiar to it as belonging to it, it also classifies them as foreign bodies and begins to treat them as such. What follows is also the actually quite normal cascade-like defense reaction of the body, which is necessary for survival – only now the body’s own structures are attacked and fought.
Causes of Goodpasture’s syndrome
The development of an autoimmune disease can have many different causes. There are, for example, certain genetically determined and therefore hereditary autoimmune diseases. Others are acquired, for example through a previous infection with bacteria or viruses.
Still others can also be triggered by toxic substances with which one has come into contact. Last but not least, in a large number of cases it is simply unclear and no other trigger can be identified. In Goodpasture’s syndrome, the causes are completely unclear, but it is assumed that there are a number of triggering factors that work together.
Apparently, the patient’s previous illnesses play an important role, for example influenza (as was the case with the patient of the first description in 1919 by the US pathologist Ernest Goodpasture (October 17, 1886 to September 20, 1960), here too it was the one previous influenza infection). In addition, connections with pulmonary tuberculosis were described. In Goodpasture’s syndrome, autoantibodies (mostly IgG1 and IgG4, but in 1/3 of cases also IgA and IgM) are formed in the basal membranes of the glomeruli (the smallest units of the kidney, the so-called renal corpuscles), which are also found in the lungs, in the course of an allergic-hypergenic type 2 reaction.
This explains why the same autoantibodies destroy the basement membranes of both the lungs and the kidneys. In the lungs, this leads to bleeding into the lung tissue itself and to bloody cough expectoration. In the kidneys, blood passes into the (primary) urine and hematuria occurs.
In Goodpasture’s syndrome, the body starts to produce antibodies against the basement membrane (which are therefore called anti-GBM antibodies), which eventually leads to severe damage to the kidneys and lungs. As a result of kidney involvement, sooner or later the affected person may develop hematuria, i.e. blood in the urine, and suffer from hypertension (since the kidney is an essential component of the human circulatory system). In Goodpasture’s syndrome, the body starts to produce antibodies against the basement membrane (which are therefore called anti-GBM antibodies), which eventually leads to severe damage to the kidneys and lungs. As a result of kidney involvement, sooner or later the affected person may develop hematuria, i.e. blood in the urine, and suffer from hypertension (since the kidney is an essential part of the human circulatory system). Goodpasture’s syndrome is diagnosed by the laboratory chemical detection of antibasement membrane antibodies and immunoglobulin deposits on the basement membranes of the glomerula, which are taken in a kidney biopsy of one or both kidneys.
