What Is The Prognosis For Lupus Nephritis?
Renal involvement is recognized as one of the most serious complications in systemic lupus erythematosus (SLE), which often occurs within the first five years of the disease and is one of the predictors of morbidity and mortality.
The prognosis of patients with systemic lupus erythematosus has improved significantly in the last decades. Survival of patients with lupus nephritis has also increased to more than 80% at 5 years in the 90´s compared to the previous 50% reported in the 60´s.
The improvement is particularly marked in the proliferative types of glomerulonephritis and can be attributed to early recognition and diagnosis as well as to the use of therapies such as cytotoxic agents and greater access to dialysis and to the transplant.
Numerous epidemiological studies in patients with lupus nephritis (LN) have been published and more than thirteen independent risk factors predictive of progression have been identified. These include age, sex, race, socioeconomic factor, genetic polymorphisms, anti-ds-DNA antibodies, antiphospholipid antibodies, anti-C1q antibodies, class histopathology, activity and chronicity indexes (AI and CI respectively), tubular atrophy, capillary thrombosis, histopathology transformation, elevated creatinine levels, nephrotic syndrome, persistent hypertension, lack of clinical remission in the first year, hypocomplementemia, the delay and the type of instituted treatment, renal outbreaks and lack of adherence to treatment.
African-American, Hispanic-American ethnicity and Latin American mestizos have been identified as factors of poor renal prognosis with a survival of 58% at 5 years independent of treatment. The presence of certain genetic polymorphisms could explain this result although the socioeconomic status and the lack of accessibility to health services are facts that cannot be ignored in this population.
Age and sex have been identified as non-modifiable factors. The earliest age at presentation and the male sex have been described as indicators of poor prognosis in adult series. The renal outbreaks are usually preceded by an increase in the titles of the anti-ds-DNA and predict the occurrence of proliferative glomerulonephritis. In this way, anti-ds-DNA plays a role in renal prognosis by predisposing to more severe forms and outbreaks of the disease.
Antiphospholipid antibodies have been implicated as a negative prognostic factor in renal survival in 2 recent studies. However, the role of these in the prognosis of lupus nephritis has not been clearly established.
The relationship between the histological findings and the clinical evolution of LN has been well recognized. Patients with mesangial glomerulonephritis (Class II) and pure membranous (Class V) generally have better renal prognosis as well as a slow deterioration of renal function over time. In contrast, glomerulonephritis proliferative (Class III and IV) are associated with a more aggressive evolution with a deterioration of renal function in the majority of patients. This rule cannot be taken into account in subsequent renal outbreaks or in the histological transformation that may occur since in these cases the prognosis depends on the new renal histology and the response to treatment.
The AI and CI have been indicators of deterioration of the renal function in different studies but these are subject to inter-observer differences and have limited reproducibility. Some studies have not been able to find a clear cutoff point for the indices that are clinically useful for predicting renal failure and mortality.
Due to the fluctuation of the pathological process in LN and the potential reversibility of some histological lesions, the prognostic factors may differ depending on the time of performing the renal biopsy and the performed treatment. Laboratory findings that predict renal prognosis have been widely studied. The elevation of serum creatinine and nephrotic syndrome in the presentation of lupus nephritis, as well as persistent hypertension, low hematocrit, hypocomplementemia and failure to achieve remission in the first year of treatment, are all significant factors.
However, patients with acute renal failure can respond completely to treatment and remain in long-term remission.
In conclusion, the renal prognosis is influenced for multiple factors in lupus nephritis where ethnicity and socioeconomic status, as well as clinical presentation, immunological profile, histopathology and initial response to treatment, should be considered. In fact, the effects of different treatment regimens have influenced the prognosis in lupus nephritis.