Renal Manifestations of Syphilis

Introduction:

Syphilis is a sexually transmitted disease. The causative agent is the spirochaete Treponema pallidum. The cases of syphilis are rising worldwide. It has been documented in the literature as a great imitator due to the wide range of clinical manifestations that can be seen in the disease. Renal manifestations are rare. However, these features are seen in secondary syphilis. It can lead to tubular pathology, vasculitic lesions, and glomerulopathies in the kidney. Membranous nephropathy is the most frequently occurring glomerular lesion associated with syphilis.

This disease can affect multiple organ systems in the body, and its manifestations can mimic a wide range of other medical conditions. While syphilis primarily targets the skin and mucous membranes, its insidious nature means it can also lead to renal (kidney) complications. Membranous nephropathy is the most commonly seen glomerular lesion in syphilis patients. Circulating immune complexes are observed among patients with secondary syphilis, and immune complexes consisting of anti-treponemal antibodies have been eluted from renal biopsy specimens. Symptoms of kidney disease might include nausea, fatigue, foamy urine, and ammonia-smelling breath and might lead to renal failure, cardiac failure, and death. This article explains the renal manifestations of syphilis, shedding light on this often-overlooked aspect of the disease.

What Is Syphilis?

Before delving into its renal manifestations, let us first understand syphilis. This infectious disease progresses through four stages:

• Primary Syphilis: This stage typically begins with the appearance of a painless sore or ulcer called a chancre, which is usually located at the site of infection (genitals, anus, mouth). If left untreated, the infection progresses to the next stage.

• Secondary Syphilis: This stage involves various systemic symptoms, including skin rashes, mucous membrane lesions, fever, and swollen lymph nodes. These symptoms may resolve independently, but the bacterium remains in the body, progressing to the latent stage if left untreated.

• Latent Syphilis: In this stage, there are no visible symptoms, but the bacterium still resides in the body, potentially causing damage to various organs over time.

• Tertiary Syphilis: This is the most severe stage that causes the development of severe, life-threatening complications that can affect the heart, brain, nerves, and other organs. The progression to tertiary syphilis can take several years.

What Are the Renal Manifestations of Syphilis?

Renal involvement in syphilis is a rare but serious complication. It is most commonly observed in the late stages of the disease, particularly in tertiary syphilis. The kidneys can be affected in several ways, leading to various renal manifestations:

• Glomerulonephritis: Syphilis-induced glomerulonephritis can lead to kidney damage and impaired renal function. This condition can manifest as hematuria (blood in the urine), reduced urine output, and high blood pressure. If left untreated, it can lead to chronic kidney disease (CKD).

• Nephrotic Syndrome: Nephrotic syndrome is a condition that is caused by excessive loss of protein in the urine, resulting in edema (swelling) and low levels of proteins in the blood. Syphilis can cause glomerulonephritis, an inflammation of the tiny filtering units in the kidneys (glomeruli). This inflammation disrupts the normal filtration process, leading to proteinuria (protein in the urine) and nephrotic syndrome.

• Interstitial Nephritis: It is the inflammation of the kidney's interstitial tissue, which surrounds the tubules. Syphilis can cause interstitial nephritis, leading to kidney dysfunction. Patients with interstitial nephritis may experience symptoms such as fever, rash, and joint pain in addition to renal impairment.

• Ureteral Strictures: Syphilis can cause inflammation and scarring of the ureters (the tubes connecting the kidneys to the bladder). Ureteral strictures can obstruct urine flow from the kidneys to the bladder, causing hydronephrosis (kidney enlargement due to urine buildup) and kidney damage.

• Syphilitic Nephritis: In some cases, syphilis can directly affect the kidney tissue, leading to syphilitic nephritis. This condition is characterized by the formation of gummas, which are granulomatous lesions that can develop in various organs, including the kidneys. Gummas in the kidneys can cause pain, reduced renal function, and other renal complications.

How to Diagnose and Treat Renal Manifestations of Syphilis?

Diagnosing renal manifestations of syphilis can be challenging due to the disease's ability to mimic other conditions. Healthcare providers usually depend on a combination of clinical evaluation, serologic tests for syphilis, and imaging studies to assess kidney function and structure. A biopsy may be necessary in some cases to confirm the presence of syphilis-related kidney damage.

Once diagnosed, treatment typically involves antibiotics, most commonly penicillin. The choice of antibiotic and duration of treatment might differ depending on the stage and severity of the disease. In cases of severe kidney involvement, such as glomerulonephritis or interstitial nephritis, corticosteroids may be prescribed to reduce inflammation and prevent further damage. It is crucial for individuals diagnosed with syphilis to complete the full course of antibiotic treatment, as failure to do so can cause treatment failure and the development of antibiotic-resistant strains of the bacterium.

How to Prevent Renal Manifestations of Syphilis?

Preventing syphilis, and consequently its renal manifestations, primarily involves safe sexual practices, including the use of condoms and regular testing for sexually transmitted infections (STIs). Early detection and treatment of syphilis are key to preventing the progression to tertiary syphilis and its associated complications, including renal damage.

Public health initiatives aimed at increasing awareness, education, and access to testing and treatment for syphilis are essential in reducing its prevalence and associated complications. Additionally, healthcare providers should remain vigilant and consider syphilis as a possible cause when evaluating patients with unexplained renal abnormalities.

Conclusion:

Renal manifestations of syphilis are rare but serious complications that can lead to kidney damage and impairment of renal function. This "great imitator" of a disease can be challenging to diagnose due to its ability to mimic various other conditions. However, timely diagnosis and appropriate treatment with antibiotics are essential in preventing further kidney damage and complications. Public health efforts, including education, prevention, and early detection, are crucial in reducing the prevalence of syphilis and its associated renal complications. Practicing safe sex, regular testing for STIs, and raising awareness about syphilis can all contribute to a decrease in its incidence and its devastating consequences on the kidneys and other organs.