Human Metapneumovirus (HMPV) Raises Concerns Over Kidney Health Amid Rising Infections

Human Metapneumovirus (HMPV) is making headlines due to an increase in infections across regions, particularly in China and India. While the virus is primarily known for affecting the respiratory system, experts are now warning about its potential to cause severe complications, including acute kidney injury (AKI), especially in vulnerable individuals such as infants, the elderly, and those with weakened immune systems.

As respiratory illness season intensifies, there are growing concerns about the spread of HMPV. Although it shares some similarities with COVID-19, experts emphasize that there’s no immediate threat of a pandemic. The virus causes flu-like symptoms such as fever, cough, nasal congestion, and difficulty breathing, but for some, it can lead to serious complications, particularly in high-risk groups.

What is Human Metapneumovirus (HMPV)?

Human Metapneumovirus (HMPV) is a respiratory virus that primarily affects the upper and lower respiratory tracts. It causes symptoms like fever, cough, nasal congestion, and difficulty breathing, and is commonly mistaken for other respiratory infections. While HMPV is typically mild in most cases, certain individuals may experience severe health issues, including kidney-related problems.

Can HMPV Affect the Kidneys?

While HMPV primarily targets the respiratory system, it can have indirect effects on the kidneys, especially in more severe cases. Experts highlight that the virus may cause complications such as cytokine storms, which occur when the immune system overreacts to the infection. This severe immune response can damage organs, including the kidneys, though direct kidney involvement with HMPV remains rare.

Cytokine Storm and Kidney Damage
Dr. Anuja Porwal, Director of Nephrology at Fortis Hospital in Noida, explains that cytokine storms can lead to multisystem organ involvement, making kidneys susceptible to damage. Although kidney function usually recovers once the infection is under control, some patients may require dialysis in extreme cases.

Evidence of Acute Kidney Injury (AKI)

There is some research suggesting a connection between HMPV and acute kidney injury (AKI), particularly among hospitalized children. Dr. Mohit Khirbat, a Consultant Nephrologist at CK Birla Hospital, Gurugram, points out a study indicating that HMPV infections in children may increase the risk of AKI. However, more research is needed to fully understand the link between HMPV and kidney disease.

Hypoxia and Kidney Function
Dr. Nikhil Modi, Senior Consultant for Respiratory Critical Care at Indraprastha Apollo Hospital, adds that severe respiratory infections caused by HMPV can lead to hypoxia (low oxygen levels), which reduces blood flow to the kidneys and further compromises kidney function. Dehydration caused by fever, vomiting, or a lack of fluid intake during the illness can also strain the kidneys, increasing the risk of kidney damage.

Who is at Risk?

People with pre-existing kidney conditions or other risk factors are particularly vulnerable to kidney-related complications from HMPV. For the majority of patients, kidney involvement remains mild, but it is important to monitor for signs of kidney dysfunction, especially in those with underlying health issues.

Signs and Symptoms of Kidney Problems in HMPV Infections

When HMPV affects the kidneys, it can cause a range of symptoms related to kidney dysfunction. These include:

• Decreased urine output
• Swelling, particularly in the legs, face, or around the eyes
• Fatigue
• Confusion
• Elevated levels of creatinine or urea in blood tests

Dr. P.S. Vali, Senior Consultant Nephrologist at the Asian Institute of Nephrology and Urology in Hyderabad, advises that patients experiencing symptoms like reduced urine output, facial puffiness, or leg swelling should undergo tests to assess kidney function, such as serum creatinine, blood urea, and a complete urine examination.

How HMPV Impacts Kidney Health

While HMPV does not directly infect kidney cells, complications from the infection can put strain on the kidneys:

• Dehydration: Caused by high fever or reduced fluid intake, which can impair kidney function.
• Sepsis: A severe infection that can lead to reduced blood flow to the kidneys, causing damage.
• Inflammation: The body’s immune response can cause inflammation that affects kidney function.

What to Watch Out For

According to Dr. Khirbat, key kidney-related symptoms to watch for during an HMPV infection include:

• Decreased urine production, which may signal kidney impairment.
• Swelling, especially in the legs, ankles, or face, which could indicate fluid retention due to kidney dysfunction.
• Fatigue and shortness of breath, which could be related to kidney issues or fluid retention.
• Nausea and vomiting, which may sometimes indicate kidney problems.

Preventing Kidney Complications

Dr. Vali recommends taking a few simple steps to reduce the risk of kidney failure during an HMPV infection:

• Stay hydrated by drinking plenty of fluids to avoid dehydration.
• Avoid unnecessary use of painkillers, and use paracetamol for general pain relief, as it is considered safe for the kidneys.
• Be vigilant for signs of kidney dysfunction, such as decreased urine output, swelling, and fatigue.

Conclusion

Although direct kidney involvement in HMPV infections is uncommon, the virus can indirectly affect kidney function, especially in severe cases. Monitoring symptoms and seeking early medical intervention can help prevent long-term kidney damage. As always, individuals with pre-existing kidney conditions should take extra precautions and consult healthcare professionals if they suspect complications from an HMPV infection.