Long COVID is not simply lingering fatigue. It is a multisystem disorder involving impaired microcirculation, fibrinoid microclots, vascular dysfunction, and immune dysregulation. At St. George Hospital, we identify and treat these mechanisms directly.
Post-COVID syndrome — commonly known as Long COVID — affects an estimated 65 million people worldwide. Symptoms persist for months or years after initial infection, disrupting patients’ ability to work, exercise, and carry out daily life.
At St. George Hospital in Bad Aibling, Germany, under the clinical leadership of Dr. Julian Douwes, we approach Post-COVID not as a vague collection of unexplained symptoms, but as a condition with identifiable, measurable pathology. Our diagnostic and treatment protocols are informed by the latest clinical research, including the work of Dr. Beate Jaeger, whose investigations into fibrinoid microclots and endothelial dysfunction have shaped how we understand and address the biological mechanisms driving Long COVID.
We believe that effective treatment begins with accurate diagnosis. Our program combines advanced laboratory assessment, functional microcirculation testing, immune profiling, and targeted biological therapies to address the root causes of persistent illness.
The clinical work of Dr. Beate Jaeger at Klinik St. Georg has been instrumental in highlighting the role of fibrinoid microclots in Post-COVID syndrome. Her research points to endothelial dysfunction and impaired microcirculation as key mechanisms underlying the persistent symptoms experienced by Long COVID patients.
Microclots — abnormal, amyloid-like fibrin deposits found in the blood of Post-COVID patients — trap inflammatory molecules and impair oxygen and nutrient delivery to tissues throughout the body. When the endothelium (the lining of blood vessels) is damaged, the resulting vascular dysfunction compounds these effects, creating a self-perpetuating cycle of inflammation and hypoxia at the capillary level.
This pathophysiological framework directly informs the treatment approach at St. George Hospital. By targeting microclots through therapeutic apheresis, supporting vascular repair, and restoring adequate microcirculation, we address the condition at a mechanistic level rather than managing symptoms alone.
Note: The microclot and microcirculation model represents an important and clinically relevant research direction. These mechanisms are actively under scientific investigation, and our treatment protocols evolve as the evidence base develops.
Current clinical evidence points to several interconnected mechanisms that sustain Post-COVID symptoms. Understanding these pathways is essential to effective treatment.
Abnormal amyloid-like fibrin deposits form in the blood, trapping inflammatory proteins such as serum amyloid A and alpha-2 antiplasmin, resisting normal breakdown and obstructing capillary flow.
The vascular endothelium -- the single-cell lining of all blood vessels -- sustains damage from SARS-CoV-2 infection, impairing vasodilation, increasing clotting tendency, and promoting chronic inflammation.
Capillary blood flow is reduced, limiting oxygen and nutrient delivery to tissues throughout the body. This microcirculatory failure contributes to fatigue, cognitive dysfunction, and organ-level symptoms.
Chronic immune activation, elevated inflammatory cytokines, reactivation of latent viruses (EBV, CMV, HHV-6), and emerging autoimmune phenomena sustain systemic inflammation long after viral clearance.
Cellular energy production is impaired at the mitochondrial level, resulting in reduced ATP synthesis, increased oxidative stress, and the profound fatigue and exercise intolerance characteristic of Long COVID.
The autonomic nervous system -- which regulates heart rate, blood pressure, digestion, and temperature -- becomes dysregulated, leading to POTS, orthostatic intolerance, and erratic vital signs.
Based on the microclot and microcirculation framework, our Post-COVID treatment protocol combines targeted biological therapies to address each pathological mechanism. Treatment plans are designed by Dr. Julian Douwes and individualized for each patient.
Heparin-induced extracorporeal LDL precipitation removes microclots, inflammatory proteins, and fibrinogen from the blood, directly addressing the microclot burden identified by Dr. Beate Jaeger's research.
Pressurized oxygen therapy saturates tissues beyond what impaired microcirculation can deliver, supporting neurological recovery, endothelial repair, and reduction of chronic inflammation.
Alternating low and high oxygen breathing stimulates mitochondrial biogenesis, improves cellular energy production, and enhances the body's adaptive capacity at the metabolic level.
Intravenous immune support, targeted cytokine modulation, and biological immune regulation address the chronic immune dysregulation and viral reactivation that sustain Long COVID symptoms.
Medical ozone administration improves blood rheology, enhances oxygen utilization at the tissue level, and exerts antimicrobial and immune-modulating effects relevant to Post-COVID recovery.
Carefully paced physical rehabilitation, respiratory training, and autonomic reconditioning are essential to rebuilding functional capacity without triggering post-exertional malaise.
Understand the full spectrum of Long COVID symptoms organized by organ system, and the biological mechanisms -- from microclots and endothelial damage to viral persistence -- that drive them.
Our three-phase treatment approach: precision diagnostics, core biological therapies targeting microclots and microcirculation, and long-term recovery and resilience building.
Begin with a comprehensive evaluation. We accept international patients and offer teleconsultation for initial assessment before your visit to Bad Aibling.
Our Post-COVID recovery program is typically 2-3 weeks, depending on the severity of your symptoms and the specific therapies included in your individualized treatment plan. Some patients benefit from a follow-up stay several months later.
Our diagnostic evaluation includes microcirculation assessment, microclot detection, comprehensive immune profiling, mitochondrial function testing, autonomic nervous system evaluation, inflammatory marker panels, and screening for viral reactivation (EBV, CMV, HHV-6). Additional tests are ordered based on individual clinical findings.
“Our son is back to full health. He is doing all the sport he loves, back to full time schooling and he is happier than he has ever been. He even competed at an athletics competition and broke some records and received many medals. Thank you for helping our boy get his life back. Keep up the amazing work you are doing, you are changing lives and giving children back their futures.”
International Patient’s Parent, Ireland
Post-COVID Recovery
International Patient
Post-COVID syndrome is treatable. Contact our team to discuss your symptoms, review your medical history, and explore your treatment options.
