Nephrotic syndrome is a serious kidney disorder that is characterized by hypoalbuminemia, proteinuria, and edema. It can be either primary or secondary. In the former case, it refers exclusively to the kidneys while in the latter case, it reflects the general organism’s illness. The well-developed and integrative approach is necessary for maximizing the long-term results and minimizing the corresponding risks. The present paper examines etiology, incidence, physiopathology, signs, symptoms, and complications.
The etiology of nephrotic syndrome includes various types of kidney diseases including focal glomerulosclerosis, membranous nephropathy, etc. The above types of kidney diseases are classified as primary causes of nephrotic syndrome because it can be their direct consequence. Some factors also increase the likelihood of nephrotic syndrome although their impact is indirect. In particular, amyloidosis and diabetes mellitus may be considered as being secondary causes of the syndrome. Moreover, the hereditary factors may also impact the development of the syndrome. In the vast majority of cases, the combined effects of several primary and secondary factors are observed.
Nephrotic syndrome is a comparatively rare disease as its incidence is around 2-3 patients per 100,000 of the adult population. Children face lower risks in comparison with adults in relation to the potential developing of thromboembolism; the corresponding probabilities are equal to 2.8% and 26.7% respectively. The distribution of risks depends on the age as well as the presence of membranous histologic changes. Children aged above 12 years and infants face higher risks than other groups of children. The highest degree of risk is observed among adults with membranous nephropathy (37%). Thus, the incidence of nephrotic syndrome depends on various factors, and its distribution among various population groups is non-linear.
The physiopathology of nephrotic syndrome is complicated and differs substantially from other syndromes. The glomerular filtration barrier performs important functions in the healthy organism preventing the over-concentration of proteins in urine. However, the functioning of the barrier is affected substantially due to nephrotic syndrome. The reason is that homogenous crystalline elements emerge within cells. Correspondingly, albumin and other proteins escape from the filter and appear in urine. As a result, its concentration rises dramatically (from no more than 50 mg per day to around to 500 mg per day). It affects the functioning of all systems and may lead to hyperlipidemia.
Nephrotic syndrome may lead to the serious glomerular structural changes. It affects the basement membrane, the podocytes, and the endothelial surface. The combination of these factors depends on the specific form of nephrotic syndrome as well as the related primary, secondary, and hereditary factors. In addition, the effects of nephrotic syndrome include the formation of edema. It is caused by renal sodium retention. The decrease of sodium discretion affects the concentration of protein in a human body. Therefore, the intravascular volume may remain at the normal level for the majority of patients with nephrotic syndrome. The serum albumin concentration is often uncorrelated with sodium retention among such patients.
The changes in the albumin flows within the body affect the plasma colloid pressure. The observed effects are proportional in this context, i.e. the higher losses of protein correspond to lower pressure and vice versa. The flows of fluid depend on the hydrostatic pressure. The protein concentration influences the oncotic pressure as well as the distribution of plasma. In general, the forces affecting capillary filtration are subject to serious changes, and it creates the growing health risks at the cellular level.
Moreover, nephrotic syndrome leads to the complex metabolic consequences. The risks of infection tend to increase dramatically as the optimal distribution of plasma and proteins is disturbed. Hypercoagulability may also occur, and the tendency towards the growing blood clotting may become more intense. Hypovolemia is also often observed as the changes in the volume of plasma decrease the average blood volume. In this case, the serum albumin level should also be at the level much below the normal degree.
Hypocalcemia and bone abnormalities are also comparatively widespread as the serum albium level tends to decline with the development of the syndrome. The density of the patient’s bones tends to decline, and the urinary losses of vitamin D tend to increase. Correspondingly, the average rates of calcium absorption diminish to the unacceptable degree. The syndrome’s physiopathology also explains the likelihood of pulmonary embolism and venous thrombosis. The substantial urinary loss of proteins contributes to the further development of nephrotic syndrome.
There are several major signs and symptoms of nephrotic syndrome. The first one is edema that refers to the intense swelling especially in such areas as feet and eyes. Hypoalbuminemia is the underlying factor contributing to edema. As the level of albumin in the patient’s blood decreases substantially, it leads to the growing fluid’s concentration in tissues. The disrupted natural balance results in swelling. The second one is the potential weight gain caused by the non-optimal fluid retention. The rates of weight gain are usually closely related to the stage of nephrotic syndrome although other symptoms should also be considered. The third one is foamy urine due to the high concentration of protein in the patient’s urine. The fourth one is hypercholesterolemia that refers to very high levels of cholesterol in the patient’s blood. It emerges due to the disruption of the glomerular barrier and the possibility of several ensymes’ escape to urine.
There are several major complications associated with nephrotic syndrome. Firstly, it may lead to renal failure, and it can be either gradual or acute. In addition, the kidneys’ ability to clean the patient’s blood may decline as edema may affect the kidney tissue. Secondly, the hypercoaguable state among some patients is possible. The likelihood of blood clots rises as the patient’s blood overclots above the normal degree. Thirdly, the chronic kidney disease may emerge due to the inability of kidneys to perform their functions properly. Fourthly, there are substantial risks of malnutrition because the loss of protein may affect the patient’s weight. Finally, patients may experience a very high level of blood pressure. The reason is that the damaged glomeruli does not allow maintaining the optimal level of blood pressure, and numerous problems are possible.
To summarize, nephrotic syndrome is a serious kidney disorder that leads to the over-concentration of protein in the patient’s urine. Its etiology includes primary and secondary causes. The former refers to various chronic diseases such as membranous nephropathy, focal glomerulosclerosis, etc. The latter refers to amyloidosis and diabetes mellitus that increase the general likelihood of the syndrome although their impact is indirect. In addition, various hereditary factors also impact the development of nephrotic syndrome. The current incidence is around 2-3 patients per 100,000 of the population, and it is a comparatively low level. The syndrome’s physiopathology is complicated and mostly refers to the problems with the glomerular filtration barrier. The major signs and symptoms include edema, the weight gain, and foamy urine. The most typical complications include blood clots, renal failure, and the high blood pressure.
