Biopsy of nasal cartilage revealed loss of the cartilage matrix and a hyperplastic mucous
membrane. Jaksch von Wartenhorst considered this was an undescribed degenerative disorder of cartilage and named it Polychondropathia. He even took his patients occupation into consideration, and related the cause to excessive alcohol intake.Since then, the disease has received many names. The following table shows the history of the nomenclature of relapsing polychondritis. The current name, Relapsing Polychondritis (RP), was introduced by Pearson and his colleagues in 1960 to emphasize the episodic course of the disease. Research
There has been little research on neurological problems related to RP. If these cartilage structures get inflamed, they could press against nerves and cause a variety of problems that is seen in RP like peripheral neuropathy and many more. References
Further reading
Sanders, Lisa (14 November 2021) [10 November 2021 (online)]. "A Doctor Asks Two Strange Questions That Reveal a Mysterious Disease". The New York Times Magazine. p. 22. Retrieved 10 November 2021. Trentham DE, Le CH (July 1998). "Relapsing polychondritis". Ann. Intern. Med. 129 (2): 114–22. doi:10.7326/0003-4819-129-2-199807150-00011. PMID 9669970. S2CID 31763543. Archived from the original on 2014-11-08. Retrieved 2006-06-20.
Peripheral cyanosis may be due to the following causes:
All common causes of central cyanosis
Reduced cardiac output (e.g. heart failure or hypovolemia)
Cold exposure
Chronic obstructive pulmonary disease (COPD)
Arterial obstruction (e.g. peripheral vascular disease, Raynaud phenomenon)
Venous obstruction (e.g. deep vein thrombosis)

Differential cyanosis
Differential cyanosis is the bluish coloration of the lower but not the upper extremity and the head. This is seen in patients with a patent ductus arteriosus. Patients with a large ductus develop progressive pulmonary vascular disease, and pressure overload of the right ventricle occurs. As soon as pulmonary pressure exceeds aortic pressure, shunt reversal (right-to-left shunt) occurs. The upper extremity remains pink because deoxygenated blood flows through the patent duct and directly into the descending aorta while sparing the brachiocephalic trunk, left common carotid, and left subclavian arteries. Evaluation
A detailed history and physical examination (particularly focusing on the cardiopulmonary system) can guide further management and help determine the choice of testing to be performed. Tests that can be performed include pulse oximetry, arterial blood gas, complete blood count, methemoglobin level,  electrocardiogram, echocardiogram, X-Ray, CT scan, cardiac catheterization, and hemoglobin electrophoresis. In newborns, peripheral cyanosis typically presents in the distal extremities, circumoral, and periorbital areas. Of note, mucous membranes remain pink in peripheral cyanosis as compared to central cyanosis where the mucous membranes are cyanotic. It is important to note that skin pigmentation and hemoglobin concentration can affect the evaluation of cyanosis. Cyanosis may be more difficult to detect on people with darker skin pigmentation.