Clinical Signs and Symptoms Flashcards
What is the following?
Acanthosis nigricans
What can cause the following?
- Type 2 diabetes
- Obesity
- Cushing’s syndrome
- Acromegaly
- Malignancy
- PCOS
- Other states of hyperinsulinaemia
What is the mechanism behind acanthosis nigricans?
The mechanism is complex, with most cases occurring in the presence of insulin resistance. This leads to hyperinsulinaemia, which in turn stimulates the proliferation of keratinocytes (which contain melanin) and fibroblasts.
What can cause atrophic testicles?
- Trauma
- Cirrhosis of the liver
- Varicocoele
- Klinefelter’s syndrome
- Prader–Willi syndrome
- Hypopituitarism
- Infection
- Anabolic steroid use
How does kelinfelters cause atrophic testicle?
Gonadotropins (LH and FSH) rise during puberty, the seminiferous tubules fibrose and shrink and may become obliterated. Hence, the volume of the testicle is reduced.
What is the mechanism behind atrophic testicles in anabolic steroid use?
Exogenous steroids cause suppression of the hypothalamic axis, in particular LH production, and therefore suppression of testosterone production, ultimately leading to atrophy.
How would you describe the following?
Cushingoid habitus
What is Chvotsek’s sign?
Tapping on the patient’s cheek at a point anterior to the ear and just below the zygomatic bone to stimulate the facial nerve results in twitching of the ipsilateral facial muscles. It is suggestive of latent tetany and increased neuromuscular excitability
What is trousseau’s sign?
After inflating a cuff above the patient’s systolic blood pressure and leaving it inflated for 3 minutes, muscular contraction – including flexion of the wrist and MCP joints, hyperextension of the fingers and flexion of the thumb on the palm – occurs
What is thought to be the mechnism of Chovtsek’s Sign in hypocalcaemia?
Increased neuronal excitability
Calcium is needed to maintain normal neuronal membrane permeability by acting on and blocking sodium channels on the neuronal membrane. If extracellular calcium is low and/or not available, the sodium channels are more permeable. As more sodium enters the cell, the cell becomes less polarised and is more easily stimulated to reach action potential
What is thought to be the mechanism behind Trousseau’s sign?
Similar mechanism to Chvostek’s sign
What are causes of the following?
- Graves’ disease
- Hashimoto’s disease
- Congenital
- Adenomatous (thyroid adenoma)
- Iodine deficiency
- Toxic multinodular goitre
- Thyroid carcinoma
What are causes of hirsuitism?
- Polycystic ovary syndrome (PCOS) – most common cause
- Cushing’s disease
- Idiopathic
- Congenital adrenal hyperplasia
- Ovarian tumours
- Adrenal tumours
- Hyperthecosis – very rare
What is the following?
Hypercarotinaemia/carotenoderma
What are causes of the following?
- Excess vegetable intake - most common
- Nephrotic syndrome
- Diabetes mellitus
- Hypothyroidism
- Hyperlipidaemia
- Porphyria
- Anorexia nervosa
- Liver disease
What is the following?
Hyperpigmentation
What can cause the following?
- Addison’s disease (ACTH-dependent causes) – very common
- Cushing’s disease (ACTH-dependent causes) – less common
- Haemochromatosis
What is the following?
Macroglossia
What could cause the following?
- Hypothyroidism – in children
- Beckwith–Wiedemann syndrome – in children
- Down syndrome
- Lymphangioma – in children
- Haemangioma – in children
- Idiopathic hyperplasia – in children
- Metabolic disorders – in children
- Amyloidosis (both primary and secondary disorders) – most common cause in adults
- Acromegaly
- Traumatic
What is the following?
Necrobiosis lipodica diabeticorum - One or more sharply demarcated yellow-brown plaques on the anterior pretibial region.
What is thought to be the cause of the following?
What is the mechanism behind periodic paralysis in hyperthyroidism?
Defects in muscle ion channels are the main cause of thyrotoxic periodic paralysis, although the how or why is unclear.99 Hyperthyroidism increases the activity of the Na+/K+ pumps on muscle cells, producing a large and rapid shift of potassium intracellularly and leading to hyperpolarisation and absent muscle cell depolarisation.
What is the following, and what can cause it?
Plethora:
- Chronic alcoholism
- Cushing’s disease
- Parenchymal lung disease
- Menopause
- Hyperthyroidism
- Polycythaemia
- Hypernephroma
- SVC obstruction
- Mitral stenosis
- Carcinoid syndrome
What is the following, and what causes it?
Prognathism - Abnormal protrusion of one or both jaws, particularly the mandible, relative to the broader facial skeleton
Caused by congenital defects or acromegaly
What is vitiligo?
A chronic disorder of the skin, usually progressive, consisting of depigmented white patches which are often surrounded by a hyperpigmented border
What are causes of the following?
- Turner’s syndrome
- Noonan’s syndrome
