Clinical presentation of acute leukemias

Intoxication and infectious syndromes

These two syndromes are closely linked to the systemic effects of the leukemic process and often present as the very first signs of the developing disease.

Intoxication syndrome is caused by the massive breakdown of tumor cells and the release of their metabolic and destruction products into the bloodstream. This systemic toxic effect leads to persistent fever, severe and rapid fatigue, and a noticeable weight loss in the patient.

Infectious syndrome also frequently becomes an early clinical manifestation. Patients develop severe tonsillitis, stubborn gingivitis and stomatitis, and pneumonia, which can rapidly progress to sepsis.

• Pathogenesis: The onset of infections is directly related to the profound suppression of normal mature granulocyte and monocyte production in the bone marrow. Furthermore, the remaining pool of lymphocytes turns out to be functionally incompetent, leaving the body without adequate immune protection.

Bone marrow failure syndromes

Cytopenic manifestations develop due to the mechanical and functional replacement of normal hematopoietic elements by the rapidly dividing blast clone.

1. Anemic syndrome

Occurs as a consequence of the profound suppression of the normal erythroid lineage of the bone marrow. Externally, this manifests as severe pallor of the skin and visible mucous membranes. Patients complain of increasing generalized weakness, and objective examination reveals compensatory tachycardia.

1. Hemorrhagic syndrome

Associated with the suppression of the platelet lineage, leading to severe thrombocytopenia. An important role in the pathogenesis is played by leukostasis, a specific intravascular embolism of vessels by lymphoblasts. Clinically, the syndrome is characterized by:

• Skin manifestations in the form of petechiae and larger ecchymoses.
• Hemorrhages into the mucous membranes and tissues of internal organs.
• Severe gastrointestinal bleeding (presentation with hematemesis and black tarry stools — melena).

Hyperplastic syndrome

The basis of this syndrome is massive specific (leukemic) infiltration of various tissues and organs by tumor lymphoblasts. A crucial feature of the process is that tissue infiltration occurs without the development of signs of true inflammation.

Main target organs and symptoms:

• Lymphoid system and abdominal organs: Generalized lymphadenopathy develops with the formation of large, dense, and completely painless conglomerates. Hepatosplenomegaly occurs, which can provoke severe abdominal pain.
• Musculoskeletal system: Infiltration of joint capsules and the periosteum leads to intense bone pain (ossalgia) and joint pain (arthralgia).
• Skin and glands: Specific dense, painless infiltrates form on the skin — leukemids. Symmetrical enlargement of the lacrimal and salivary glands, known as Mikulicz's syndrome, is also observed.
• Reproductive system: In boys, unilateral or bilateral enlargement of the testes is possible due to the formation of dense leukemic infiltrates within them.
• Visceral lesions: In the respiratory system, infiltration of the lung parenchyma, hemorrhages, and compression of the airways by enlarged mediastinal lymph nodes lead to respiratory disorders. Myocarditis and exudative pericarditis may develop in the heart. These conditions arise secondarily because lymphoblasts block normal lymphatic drainage pathways.

Neuroleukemia and other lesions

CNS involvement (neuroleukemia) occurs as a result of the migration (metastasis) of aggressive lymphoblasts into the structures of the nervous system. The clinical picture consists of severe hypertension syndrome, the appearance of meningeal signs (meningism), focal cranial nerve palsies, paresis, and the development of seizure syndrome.

Danger of latent course: If the administered therapy is insufficiently aggressive, blast cells can enter a "dormant" mode. They persist in the cerebrospinal fluid (CSF) without active division for many decades. This exact reservoir serves as the primary substrate for delayed relapses of acute leukemia.

In addition to the CNS, the visual organ is involved in the pathological process. Ophthalmological disorders manifest as decreased visual acuity. This occurs due to retinal hemorrhages in the fundus and direct specific blast infiltration of the walls of ocular vessels.

Class and exam questions

What else to study on this topic

• Mechanisms of leukostasis formation and their systemic consequences
• Mikulicz's syndrome: differential diagnosis
• Pathogenesis of exudative pericarditis in lymphoblastic infiltration
• Features of cranial nerve involvement in neuroleukemia
• Laboratory and instrumental tests to confirm the clinical diagnosis

Other topics in "Chapter 10. Diseases of the Blood and Blood-Forming Organs"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.