What is lupus nephritis?

Nephrology Specialist Doctor Kadir Gökhan ATILGAN; informs about the disease, which is more common in women and causes serious problems with kidney involvement.

Nephrology Specialist Doctor Kadir Gökhan ATILGAN, “The word lupus means wolf in Latin. The disease was given this name because it insidiously left it weak and debilitated over time, as a wolf does to its prey. Systemic lupus erythematosus (SLE), like its name, is systemic. It is a disease that progresses with involvement and progresses with rashes on the skin, which we call erythema. The most important of these system involvements is “lupus nephritis”, which we call kidney involvement. It is usually expected to develop in the 5 years following the diagnosis of SLE. SLE and lupus nephritis occur during the periods when the disease, which we call exacerbations, is active and passive. Early diagnosis is important in order not to leave permanent damage to the tissues involved during these active periods. In general, from the time the disease is diagnosed with SLE, it is necessary to be alert for kidney involvement with simple tests such as urinalysis and blood analysis

If we examine the disease in terms of its developmental process , autoimmune in a nutshell What we call te is the process of damaging itself with the body’s own weapons called antibodies. Anti-Nuclear Antibodies (ANA), Anti-dsDNA, which are the follow-up diagnostic criteria for SLE, cause accumulation directly in the glomerulus, which is a part of the nephron, the building block of the kidney. These and other antibodies with high affinity for the glomerulus, together with the inflammatory reaction they create, provide the accumulation of our defense cells, which we define as white blood cells, through the messengers we call immunoglobulin and complement. We call this immune complex formation and it creates exacerbation processes in which the disease causes permanent tissue loss if not treated.

Genetic susceptibility is an issue that is emphasized in SLE, as it is in every systemic disease. Dozens of genes have been studied. As always, the statistics taken from the data system of the USA revealed a familial prevalence of 10-12%, a predisposition of 24-52% in identical twins, and 2-5% in fraternal twins. High prevalence of SLE with HLA-DR2 and HLA-DR3 from HLA class-II genes, and low prevalence with HLA-DR4 was determined. It was determined that gene deletion in our complement factors C1q, C1r, C1s, C2, C4 deficits, and in C4a and C4b were highly correlated with SLE. In the cytokine family, it has been shown that there is a strong relationship between IL-10, IL-1RN and TNF alpha and SLE.

Regarding the prevalence of SLE, sources describe 1 person in 2000. For lupus nephritis, it is stated that 30-90% of patients with SLE will have involvement. On average, 50% of SLE patients are expected to have lupus nephritis. Changes in rates vary due to reasons such as race, gender, environmental factors. In the epidemiology study article published by Danchenko in the journal Lupus in 2007, SLE was more common in non-white populations in the USA, Canada, Europe, Asia, and Australia sample, it was more common in Europe and Australia than the USA, and the least involvement in Japan. stated that. The countries with the highest involvement in Europe were Sweden, Iceland and Spain.

We can say that SLE is a disease of women with a ratio of 9:1. SLE in men is more severe than in women, and complications are associated with tissue loss. The age of involvement is specified as 20-40 years of age. Early involvement is considered a predictor of poor prognosis.

Lupus nephritis patients present with nephrotic syndrome, edema and hypertension in the hands, legs and back of the feet. Edema can also be seen with diffuse whole body edema, which we call anasarca, and ascites, which we call accumulation in the sacral region and fluid accumulation in the abdomen. However, SLE may have weakness, rashes on the body, butterfly-like erythema on the face, fever, arthralgia, and flank pain due to serositis.

In the laboratory of lupus nephritis, biochemistry, especially urea and creatinine, complete urinalysis, and protein excretion level in the urine are evaluated. Blood count, sedimentation, ANA, anti-dsDNA, C3,C4, anti-C1q antibody titers provide information to evaluate the diagnosis and activity of the disease. CRP value remains normal even if sedimentation is high. CRP elevation is observed in SLE only in cases of arthritis or other infections. Activity indicator laboratory tests may differ according to the activation and stage of the disease. Kidney biopsy is essential for definitive diagnosis, activity evaluation and shaping the treatment. Imaging methods are used to evaluate the level of involvement of organs and to evaluate fluid accumulations in the lungs, heart, and peritoneum.

Pathological evaluation of renal biopsy is evaluated according to the guidelines published in 2003 by the International Society of Nephrology and the Renal Pathology Society (ISN/RPS). According to this report, lupus nephritis is examined in 6 stages. While renal biopsy is evaluated by the pathologist, it informs the nephrologist in terms of activity indices and chronicity indices, which are also annexed to the ISN/RPS 2003 guideline. This information is important in predicting the course of the disease and in treatment evaluations.

Although the treatment of the disease varies according to histological staging, treatment is possible.

To summarize the treatment of the disease according to the stages;

1- Class-I minimal mesangial LN: does not require immunosuppressive therapy. It is followed with supportive therapy. Within the scope of supportive treatment, antihypertensive treatment should be arranged with a blood pressure of <130/80mmHg and primarily ACE inhibitors and/or ARB group; It includes the use of statin group drugs in the presence of hyperlipidemia, hypercholesterolemia. In addition, if there are additional problems, treatments to prevent them are added.
2- Class-II mesangial proliferative LN: If urinary protein excretion is below 1000mg/day, supportive treatment can be tried, and if proteinuria is over 1000mg/day, corticosteroid therapy can be tried as a single treatment.
3- Class-III focal, Class-IV diffuse LN: it progresses rapidly to chronic renal failure if it progresses aggressively and remains untreated or inadequately treated. Therefore, corticosteroid and immunosuppressive therapy are added to supportive treatment. The immunosuppressive drug will often be cyclophosphamide or the mycophenolate salt. Azathioprine is used as a second-line drug.
4- Class-V membranous LN: it is not as aggressive as class-III and IV in terms of histology. It is usually followed by single corticosteroid therapy.

Apart from these, the search for treatment and studies are still continuing in the treatment of SLE. One of these, rituximab, which has started to be included in the guidelines, has now started to be paid in our country with its off-label form.

Lupus Nephritis Patients Can Have Kidney Transplantation Even Before Starting Dialysis.

Despite all treatments, it is recommended to prefer hemodialysis rather than peritoneal dialysis in patients with chronic renal failure and dialysis treatment. Lupus nephritis patients constitute 1.5% of the hemodialysis patient population. However, kidney transplantation, which is the most optimal of the renal replacement therapies, is possible for lupus nephritis. The only exception is to complete a process that has no activity. Even though patients are usually transplanted after the hemodialysis process, there is a chance of transplantation before the dialysis starts, which we call pre-emptive. ”