Retroperitoneal fibrosis: Symptoms, Pathogenesis, Work-ups & Treatments
Symptoms
Retroperitoneal fibrosis is one of the IgG4-related disease (IgG4-RD) with increased IgG4 antibody and is a disease in which retroperitoneum fibrosis occurs over the fourth and fifth lumbar spine. It is characterized by the appearance of retroperitoneal structures, especially ureteral stenosis. The symptoms of retroperitoneal fibrosis are nonspecific, and patients present with symptoms such as dorsal non-colicky pain, fever, weight loss, and nausea.
Pathogenesis
The pathogenesis of IgG4-related disease is still unclear. Although IgG4-RD has been detected in patients with diseases, the name IgG4-RD has emerged, but it is still unclear whether the IgG4 antibody is pathogenic. There is also a hypothesis that an increase in IgG4 is a downward process of other more important processes. The characteristics of IgG4 related disease are autoimmune and allergic. Autoimmune aspects include autoantibodies to antigens such as lactoferrin and carbonic anhydrase in type-1 autoimmune pancreatitis, the most common disease of IgG4-RD, for example. The allergenic side is that the levels of Th2 cytokines and serum IgE in IgG4-RD patients are very high and Treg is over-activated.
Retroperitoneal fibrosis, an IgG4-RD, is also unclear in its pathogenesis, but the hypothesis that it occurs through immune responses to antigens in atherosclerosis is gaining strength. Autopsy and CT reveal that Fibrosis begins around the atherosclerotic aorta, and as the middle artery becomes thinner, insoluble lipids, such as ceroid, flow to tissues around the aorta and cause an immune response. This hypothesis is supported by macrophages containing anti-seroid antibodies and ceroids found in surrounding lymph nodes.
In some cases, an immune response to an external factor may cause fibrosis. Beta-blockers, methicillides, and methyldopa act as hapten, resulting in hypersensitivity and autoimmune reactions. Considering the association of retroperitoneal fibrosis with other connective tissue diseases and the reported occurrence in the family, genetic factors also play a role in the pathogenesis. HLA-B27 appeared in several patients with retroperitoneal fibrosis.
Work-ups
As described above, the symptoms appearing in retroperitoneal fibrosis are nonspecific and the disease itself is a rare disease, making diagnosis difficult. Therefore, rather than diagnosing symptoms through the symptoms of the urinary tract stenosis or venous / arterial insufficiency, you will know about the disease by examining. CT can be used to identify characteristic features of the disease, but a biopsy may be needed for confirmation. Whether biopsy should be performed in all patients with retroperitoneal fibrosis on CT findings has not yet been established. Many doctors do not perform biopsy for patients with retroperitoneal fibrosis on CT, but biopsy is recommended when infection or malignancy is suspected.
Treatments
The goal of treatment of retroperitoneal fibrosis is to relieve fibrosis-induced stenosis, prevent progression of fibrosis and prevent recurrence. If it is due to a secondary cause, treatment aims at the treatment of the underlying etiology. If it is idiopathic, immunosuppressive treatment is done. Some patients respond to treatment within a few weeks, but the response to treatment is difficult to predict and persistent stenosis of the urinary tract can leave irreversible damage. Therefore, if serious stenosis of the urinary tract is found, it is recommended to alleviate the stenosis as soon as possible. However, therapies to relieve stenosis may lead to complications such as urinary leakage, thromboembolism, and recurrent fibrosis. Therefore, patients with unilateral hydronephrosis who are not severely impaired renal function can be treated surgically if they only use medical treatment without surgery and deteriorate renal function.
The medical treatment of retroperitoneal fibrosis depends on whether the disease is idiopathic or secondary. The goal of the treatment of secondary retroperitoneal fibrosis is to treat the underlying etiology or prevent the causative drug. Drug-induced retroperitoneal fibrosis requires discontinuation of the causative drug and improves disease within a few months. In the case of idiopathic retroperitoneal fibrosis, it is important to start with glucocorticoid monotherapy and start as soon as it is diagnosed. The pain and symptoms are relieved within a few days after the start of steroid therapy and the ESR also falls rapidly. Urinary tract stenosis and mass on CT are observed within a few weeks after the onset of medical treatment. For patients responding to steroid therapy, the mortality rate is less than 10%. For patients who do not respond well to glucocorticoid therapy for 4 to 6 months, add mycophenolate mofetil or methotrexate. Patients with serum creatinine concentrations greater than 2 mg / dL should not be prescribed methotrexate because of the risk of liver toxicity.
In this case, retroperitoneal fibrosis was diagnosed through CT and several labs after the presentation of hydronephrosis due to ureteral stenosis. Ureteral stent was inserted to relieve urinary stenosis and treated with steroids. Patients currently do not have severe symptoms due to retroperitoneal fibrosis. Therefore, it is necessary to reduce the dose of steroid after discharge and to observe the progression.
Retroperitoneal fibrosis is one of the IgG4-related disease (IgG4-RD) with increased IgG4 antibody and is a disease in which retroperitoneum fibrosis occurs over the fourth and fifth lumbar spine. It is characterized by the appearance of retroperitoneal structures, especially ureteral stenosis. The symptoms of retroperitoneal fibrosis are nonspecific, and patients present with symptoms such as dorsal non-colicky pain, fever, weight loss, and nausea.
Pathogenesis
The pathogenesis of IgG4-related disease is still unclear. Although IgG4-RD has been detected in patients with diseases, the name IgG4-RD has emerged, but it is still unclear whether the IgG4 antibody is pathogenic. There is also a hypothesis that an increase in IgG4 is a downward process of other more important processes. The characteristics of IgG4 related disease are autoimmune and allergic. Autoimmune aspects include autoantibodies to antigens such as lactoferrin and carbonic anhydrase in type-1 autoimmune pancreatitis, the most common disease of IgG4-RD, for example. The allergenic side is that the levels of Th2 cytokines and serum IgE in IgG4-RD patients are very high and Treg is over-activated.
Retroperitoneal fibrosis, an IgG4-RD, is also unclear in its pathogenesis, but the hypothesis that it occurs through immune responses to antigens in atherosclerosis is gaining strength. Autopsy and CT reveal that Fibrosis begins around the atherosclerotic aorta, and as the middle artery becomes thinner, insoluble lipids, such as ceroid, flow to tissues around the aorta and cause an immune response. This hypothesis is supported by macrophages containing anti-seroid antibodies and ceroids found in surrounding lymph nodes.
In some cases, an immune response to an external factor may cause fibrosis. Beta-blockers, methicillides, and methyldopa act as hapten, resulting in hypersensitivity and autoimmune reactions. Considering the association of retroperitoneal fibrosis with other connective tissue diseases and the reported occurrence in the family, genetic factors also play a role in the pathogenesis. HLA-B27 appeared in several patients with retroperitoneal fibrosis.
Work-ups
As described above, the symptoms appearing in retroperitoneal fibrosis are nonspecific and the disease itself is a rare disease, making diagnosis difficult. Therefore, rather than diagnosing symptoms through the symptoms of the urinary tract stenosis or venous / arterial insufficiency, you will know about the disease by examining. CT can be used to identify characteristic features of the disease, but a biopsy may be needed for confirmation. Whether biopsy should be performed in all patients with retroperitoneal fibrosis on CT findings has not yet been established. Many doctors do not perform biopsy for patients with retroperitoneal fibrosis on CT, but biopsy is recommended when infection or malignancy is suspected.
Treatments
The goal of treatment of retroperitoneal fibrosis is to relieve fibrosis-induced stenosis, prevent progression of fibrosis and prevent recurrence. If it is due to a secondary cause, treatment aims at the treatment of the underlying etiology. If it is idiopathic, immunosuppressive treatment is done. Some patients respond to treatment within a few weeks, but the response to treatment is difficult to predict and persistent stenosis of the urinary tract can leave irreversible damage. Therefore, if serious stenosis of the urinary tract is found, it is recommended to alleviate the stenosis as soon as possible. However, therapies to relieve stenosis may lead to complications such as urinary leakage, thromboembolism, and recurrent fibrosis. Therefore, patients with unilateral hydronephrosis who are not severely impaired renal function can be treated surgically if they only use medical treatment without surgery and deteriorate renal function.
The medical treatment of retroperitoneal fibrosis depends on whether the disease is idiopathic or secondary. The goal of the treatment of secondary retroperitoneal fibrosis is to treat the underlying etiology or prevent the causative drug. Drug-induced retroperitoneal fibrosis requires discontinuation of the causative drug and improves disease within a few months. In the case of idiopathic retroperitoneal fibrosis, it is important to start with glucocorticoid monotherapy and start as soon as it is diagnosed. The pain and symptoms are relieved within a few days after the start of steroid therapy and the ESR also falls rapidly. Urinary tract stenosis and mass on CT are observed within a few weeks after the onset of medical treatment. For patients responding to steroid therapy, the mortality rate is less than 10%. For patients who do not respond well to glucocorticoid therapy for 4 to 6 months, add mycophenolate mofetil or methotrexate. Patients with serum creatinine concentrations greater than 2 mg / dL should not be prescribed methotrexate because of the risk of liver toxicity.
In this case, retroperitoneal fibrosis was diagnosed through CT and several labs after the presentation of hydronephrosis due to ureteral stenosis. Ureteral stent was inserted to relieve urinary stenosis and treated with steroids. Patients currently do not have severe symptoms due to retroperitoneal fibrosis. Therefore, it is necessary to reduce the dose of steroid after discharge and to observe the progression.
