Surreal illustration symbolizing the discovery of lung cancer through Acquired Hemophilia A

Unmasking Acquired Hemophilia A: When Lung Cancer Hides Behind Bleeding

Samir D’Costa in Health & Wellness November 2025 • 4 min read.

"Discover how a rare bleeding disorder, Acquired Hemophilia A, led to an unexpected lung cancer diagnosis, changing the patient's life."

Acquired Hemophilia A (AHA) is a rare autoimmune condition characterized by the body producing antibodies that attack Factor VIII (FVIII), a crucial protein needed for blood clotting. This leads to bleeding disorders that can range from mild to severe.

AHA is considered rare, affecting approximately 1.5 people per million annually. While often idiopathic (meaning the cause is unknown), AHA can sometimes be triggered by underlying conditions such as autoimmune diseases, pregnancy, malignancies, or even certain medications. The diverse range of potential causes makes diagnosis challenging but also emphasizes the importance of comprehensive evaluation.

Now, let's dive into a compelling case study where AHA surprisingly led to the detection of lung cancer in an 82-year-old male. This case highlights the critical role clinicians play in considering paraneoplastic syndromes and conducting thorough investigations even when the initial symptoms point towards a different primary concern.

Unveiling the Case: When Bleeding Led to a Cancer Discovery

Surreal illustration symbolizing the discovery of lung cancer through Acquired Hemophilia A

In November 2013, an 82-year-old Caucasian man was admitted to the emergency department, experiencing spontaneous hematomas (bruises) on his left wrist and thigh. The patient's medical history included insulin-dependent diabetes, atrial fibrillation, a previous transient ischemic attack, hypertension, ischemic cardiomyopathy, peripheral artery disease, dyslipidemia, chronic renal insufficiency and a history of heavy smoking. Initial lab results revealed anemia and acute renal insufficiency. Despite discontinuing anticoagulants and administering vitamin K, the hematomas continued to worsen, necessitating multiple blood transfusions.

Further investigation revealed a significantly prolonged activated partial thromboplastin time (a test that measures blood clotting time) and a severely reduced Factor VIII level. The presence of a Factor VIII inhibitor confirmed the diagnosis of Acquired Hemophilia A (AHA). What followed was a series of treatments and further investigations, including a chest CT scan which revealed a suspicious lung nodule. This nodule turned out to be lung adenocarcinoma, completely unexpected based on the patient's initial presentation.

Initial Presentation: Spontaneous hematomas, anemia, and renal insufficiency.
Diagnosis: Acquired Hemophilia A (AHA) confirmed by prolonged aPTT, low Factor VIII, and presence of FVIII inhibitor.
Unexpected Discovery: Chest CT scan revealed a lung nodule, later diagnosed as adenocarcinoma.
Treatment: Immunosuppressants, followed by stereotactic radiotherapy for the lung cancer.

This case illustrates how AHA can be a presenting sign of an underlying malignancy, particularly lung cancer. The subsequent diagnosis and treatment of the lung cancer ultimately led to the remission of the AHA, highlighting the importance of considering paraneoplastic syndromes in patients with AHA.

Recognizing the Bigger Picture: Why AHA Matters in Cancer Detection

This case emphasizes the necessity for clinicians to conduct thorough investigations for underlying malignancies in patients diagnosed with Acquired Hemophilia A. Recognizing AHA as a potential clue to early cancer detection can significantly improve patient outcomes. While the association between AHA and cancer is rare, remaining vigilant for such connections can lead to timely diagnoses and more effective treatment strategies, ultimately improving the lives of those affected.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1016/j.rmr.2017.08.005, Alternate LINK

Title: Une Hémophilie A Acquise Ayant Révélé Un Cancer Du Poumon

Subject: Pulmonary and Respiratory Medicine

Journal: Revue des Maladies Respiratoires

Publisher: Elsevier BV

Authors: J. Cuilleron, P. Mas, L. Kiakouama, L. Gaillot-Durand, P. Seve, G. Devouassoux

Published: 2018-09-01

Everything You Need To Know

What is Acquired Hemophilia A (AHA) and what causes it?

Acquired Hemophilia A (AHA) is a rare autoimmune disorder where the body produces antibodies that attack Factor VIII (FVIII), a crucial protein for blood clotting. This antibody interference with Factor VIII can lead to bleeding disorders, ranging from mild to severe. The condition is rare, affecting about 1.5 people per million annually, and can sometimes be triggered by underlying conditions like autoimmune diseases, malignancies, or medications.

Can you summarize the case study where Acquired Hemophilia A (AHA) led to a lung cancer diagnosis?

The case study involved an 82-year-old man presenting with spontaneous hematomas, anemia and acute renal insufficiency. Further tests revealed prolonged activated partial thromboplastin time (aPTT), low Factor VIII levels, and the presence of a Factor VIII inhibitor, confirming Acquired Hemophilia A (AHA). A chest CT scan, part of the investigative workup, revealed a suspicious lung nodule, which was later diagnosed as lung adenocarcinoma. Immunosuppressants were used for AHA, and stereotactic radiotherapy was used for the lung cancer.

What are paraneoplastic syndromes, and how does Acquired Hemophilia A (AHA) relate to them in the context of cancer?

In the context of Acquired Hemophilia A (AHA), paraneoplastic syndromes are conditions triggered by cancer but are not directly caused by the physical effects of the tumor. In this specific situation, AHA can be a paraneoplastic manifestation of lung cancer, where the cancer triggers the immune system to produce antibodies against Factor VIII. Recognizing this connection is crucial for early cancer detection.

How significant is the association between Acquired Hemophilia A (AHA) and cancer detection, and what are the clinical implications?

While the association between Acquired Hemophilia A (AHA) and cancer, particularly lung cancer, is considered rare, recognizing this potential connection can lead to earlier cancer detection and improved patient outcomes. Clinicians should consider the possibility of underlying malignancies, especially lung cancer, in patients diagnosed with AHA. Thorough investigations and vigilance can lead to timely diagnoses and more effective treatment strategies.

What role does Factor VIII (FVIII) play in Acquired Hemophilia A (AHA), and how does its deficiency affect blood clotting?

Factor VIII (FVIII) plays a pivotal role in blood coagulation. A deficiency or inhibition of Factor VIII, as seen in Acquired Hemophilia A (AHA), disrupts the normal blood clotting process, leading to an increased risk of bleeding. The severity of bleeding can vary depending on the degree of Factor VIII inhibition. In the case of lung cancer triggering AHA, managing Factor VIII levels becomes crucial, often involving immunosuppressants and addressing the underlying malignancy to restore normal coagulation function.