Symptoms and Emergency Red Flags

While PAMI syndrome is a chronic condition, the combination of dysregulated immune signaling and low infection-fighting cells means that certain situations require immediate medical action. Understanding the difference between a typical symptom flare and a medical emergency is essential.

Common Signs and Symptoms

PAMI is a systemic condition, meaning it affects multiple parts of the body at once. Based on a 2022 review of 43 reported cases, patients may experience a wide range of symptoms that can change over time ^[1].

• Blood Count Changes: Nearly all reported patients have anemia (low red blood cells) and neutropenia (low infection-fighting white blood cells) ^[1][2].
• Skin and Joints: Skin issues like severe acne or pyoderma gangrenosum (painful skin ulcers), as well as arthritis or bone pain, are frequently observed ^[1][3].
• Organ Enlargement: The spleen and liver can become enlarged (hepatosplenomegaly) due to the systemic inflammatory process ^[1].
• Growth and Energy: Growth failure (not gaining weight or height as expected) affects many children with PAMI ^[1]. Chronic fatigue and low-grade fevers are also common ^[1].

Red Flags: When to Seek Urgent or Emergency Care

Because most children with PAMI have neutropenia, their bodies do not have enough neutrophils (a type of white blood cell) to fight off common bacteria. This makes even a simple infection potentially life-threatening ^[1]. Crucially, because of neutropenia, a patient may not develop a high fever even during a serious infection.

1. Febrile Neutropenia and Sepsis

If a fever occurs while the neutrophil count is low, this is a medical emergency called febrile neutropenia. In this state, an infection can turn into sepsis very quickly ^[4].

Follow your clinic’s individualized written sick plan immediately. Seek emergency evaluation for:

• A fever that meets your specific clinic’s threshold (do not wait an hour if your team has instructed you to go immediately) ^[1].
• Shaking chills or shivering.
• Extreme sleepiness, confusion, or difficulty waking up.
• Rapid breathing or a racing heart.
• Cool, pale, or “mottled” (blotchy) skin.

2. New or Worsening Skin Ulcers and Joint Swelling

It is dangerous to assume that a new ulcer or a swollen joint is simply a “routine flare” if the patient has neutropenia. A skin, soft-tissue, or joint infection can be serious even when the child initially looks well and has no fever.

• Immediate contact or same-day assessment is required for new or rapidly worsening skin ulcers, redness, warmth, drainage, severe pain, or inability to use a limb ^[1]. Do not wait for a fever to develop.

3. HLH and Macrophage Activation Syndrome (MAS) Warning Signs

In rare cases, the immune system in PAMI can go into a state of extreme, life-threatening overactivity called HLH (Hemophagocytic Lymphohistiocytosis) or MAS (Macrophage Activation Syndrome) ^[5][6]. This is a rapid deterioration that damages organs.

These are warning signs that require urgent clinical assessment, not for you to diagnose alone:

• A persistent, high fever that does not go away.
• A rapidly swelling abdomen ^[7].
• Easy bruising or unusual bleeding ^[8].
• Yellowing of the skin or eyes (jaundice).

Symptom Progression Over Time

PAMI symptoms often begin in early childhood, with a median age of around 4 years old, though they can appear at any age ^[1]. Over time, some symptoms may improve with treatment, while others—particularly the low blood counts—often persist ^[2][3].

As the patient grows, the medical team will also monitor for less common but serious long-term complications, such as pulmonary hypertension (high blood pressure in the lungs) or kidney issues, which may present as shortness of breath or changes in urination ^[9][10]. Always report any new or worsening breathing difficulties or swelling to your doctor immediately.