Primary syndrome in clinical practice

Primary hypothyroidism and thyroid deficiency syndrome

Thyroid hormone deficiency syndrome clinically manifests as myxedema. The basic clinical picture consists of a characteristic triad: neuropsychiatric disorders, bradycardia, and a specific edematous syndrome affecting the face, trunk, and extremities.

Etiological factors of the syndrome development:

• Primary glandular lesion: includes idiopathic organ atrophy and autoimmune thyroiditis (Hashimoto's thyroiditis).
• Iatrogenic causes: develop as a consequence of thyrotoxicosis treatment (status post subtotal thyroidectomy or radioactive iodine therapy).
• Drug-induced disorders: occur against the background of prolonged administration of specific drugs, such as lithium, amiodarone, or iodine preparations.
• Central causes: are associated with hypofunction of the hypothalamic-pituitary system.

Pathogenetic basis: The resulting deficiency of thyroid hormones inevitably leads to a global decrease in oxidative processes in the body. This causes a profound disruption of absolutely all types of metabolism and leads to the massive accumulation of mucopolysaccharides in tissues, which is clinically expressed as mucous edema.

Skin manifestations of systemic pathologies and metabolic disorders

Visual inspection of the skin and mucous membranes allows for the identification of markers of serious primary and systemic diseases:

1. Antiphospholipid syndrome (APS). A laboratory sign is the detection of anticardiolipin antibodies. Clinically, the syndrome manifests as recurrent thrombosis of cerebral and pulmonary vessels, microcirculatory thrombosis (primarily affecting the kidneys), and severe obstetric pathology in the form of recurrent pregnancy loss.
2. Dyslipidemias. The pathogenesis of skin markers is associated with the accumulation of phagocytes overloaded with cholesterol and/or triglycerides. These changes are associated with atherosclerosis (including familial forms) and liver pathology (specifically, primary biliary cholangitis). The following forms are distinguished:
3. Xanthomas: tuberous thickenings localized in the projection of joints and Achilles tendons.
4. Xanthelasmas: yellowish-orange, often elevated spots on the eyelids, oral mucosa, and auricles.
5. Senile corneal arcus: an additional sign of atherosclerosis detected during eye examination.
6. Purine metabolism disorders (gout). Gouty tophi are formed — dense, completely painless tuberous formations consisting of deposits of amorphous uric acid salts. They are localized on the auricles and in the joint area, often causing severe deformation of the latter.
7. Vascular markers of liver damage. Telangiectasias (spider angiomas) represent local excessive dilation of capillaries and small blood vessels. They have high diagnostic value as a characteristic sign of chronic liver diseases, especially cirrhosis.

Extraintestinal manifestations of inflammatory bowel disease

Extraintestinal manifestations of inflammatory bowel disease (IBD) can affect virtually all organ systems of the patient.

Pathogenesis and clinical features: The onset of these conditions is closely associated either with the activity of the primary inflammatory process directly in the intestine or with developing malabsorption syndrome. In some cases, extraintestinal lesions can proceed as completely independent immune-mediated conditions. They drastically reduce the patient's overall quality of life, and some of them pose a direct threat to life (e.g., severe thromboembolism or primary sclerosing cholangitis).

Main nosological forms and targets:

• Articular syndrome: manifests as peripheral arthritis and sacroiliitis.
• Skin and mucous membranes: development of erythema nodosum (erythema nodosum) and aphthous stomatitis.
• Organs of vision: occurrence of uveitis and episcleritis.
• Hepatobiliary system: formation of such a severe condition as primary sclerosing cholangitis (PSC).
• Vascular system: occurrence of various vascular disorders.

Differential diagnosis of bronchial obstruction syndrome in children

Bronchial obstruction syndrome in young children (specifically, acute bronchiolitis) requires a thorough differential search with a number of pathological conditions that present with a similar clinical picture.

The specific feature of the first months of a patient's life is that the clinical picture mimicking bronchial asthma is most often caused by congenital anomalies and hereditary diseases. Therefore, acute bronchiolitis is always among the conditions requiring the exclusion of occult primary pathology.

The spectrum of conditions for differential diagnosis includes:

• Foreign body aspiration.
• Cystic fibrosis (CF).
• Primary ciliary dyskinesia.
• Various malformations of the bronchial tree (such as tracheomalacia and bronchomalacia).
• Vascular anomalies (e.g., vascular rings that mechanically compress the airways).

Class and exam questions

What else to study on this topic

• Pathogenesis of mucopolysaccharide accumulation in primary hypothyroidism
• Mechanisms of renal microcirculatory thrombosis formation in APS
• Association of primary biliary cholangitis with lipid metabolism disorders
• Immune-mediated mechanisms of sacroiliitis and erythema nodosum development in IBD
• Clinical features of primary ciliary dyskinesia in young children

Other topics in the "Additional Topics" section

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