Löfgren syndrome is a type of acute sarcoidosis

Sarcoidosis

Sarcoidosis , also called sarcoid, Besnier-Boeck disease or Besnier-Boeck-Schaumann disease, is a disease in which abnormal collections of chronic inflammatory cells form as nodules in multiple organs. The cause of sarcoidosis is unknown...

 that is frequent in Scandinavian, Irish, African and Puerto Rican women.

It was characterized in 1953.

Some have considered the condition to be imprecisely defined.

Presentation

It is characterized by enlargement of the lymph node

Lymph node

A lymph node is a small ball or an oval-shaped organ of the immune system, distributed widely throughout the body including the armpit and stomach/gut and linked by lymphatic vessels. Lymph nodes are garrisons of B, T, and other immune cells. Lymph nodes are found all through the body, and act as...

s near the inner border of the lungs

Borders of the lung

The anterior border of the lung is thin and sharp, and overlaps the front of the pericardium. The anterior border of the right lung is almost vertical, and projects into the costodiaphragmatic recess; that of the left lung presents, below, an angular notch, the cardiac notch, in which the...

 (called "hilar

Hilum of lung

Above and behind the cardiac impression is a triangular depression named the hilum, where the structures which form the root of the lung enter and leave the viscus. These include the pulmonary artery, superiormost on the left lung, the superior and inferior pulmonary veins, lymphatic vessels and...

 lymphadenopathy

Lymphadenopathy

Lymphadenopathy is a term meaning "disease of the lymph nodes." It is, however, almost synonymously used with "swollen/enlarged lymph nodes". It could be due to infection, auto-immune disease, or malignancy....

") as seen on x-ray

X-ray

X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...

, and tender red nodules (erythema nodosum

Erythema nodosum

Erythema nodosum is an inflammation of the fat cells under the skin characterized by tender red nodules or lumps that are usually seen on both shins...

) are classically present on the shins, predominantly in women. It may also be accompanied by arthritis

Arthritis

Arthritis is a form of joint disorder that involves inflammation of one or more joints....

 (more prominent in men) and fever

Fever

Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...

.

Löfgren syndrome consists of the triad of erythema nodosum

Erythema nodosum

Erythema nodosum is an inflammation of the fat cells under the skin characterized by tender red nodules or lumps that are usually seen on both shins...

, bilateral hilar adenopathy on chest radiograph, and arthritis.

Prognosis

Löfgren syndrome is associated with a good prognosis,with >90% of patients experiencing disease resolution within 2 years.

In contrast, patients with the disfiguring skin condition lupus pernio

Lupus pernio

Lupus pernio is a chronic raised indurated lesion of the skin, often purplish in color. It resembles frostbite as it is seen on ears, cheeks, lips, nose, hands, fingers and forehead. It is pathognomonic of sarcoidosis. Microscopically, it resembles lupus vulgaris...

or cardiac or neurologic involvement rarely experience disease remission.

Genetics

Recent studies have demonstrated that the HLA-DQB1*0201 is strongly associated with Löfgren syndrome.

It is associated with HLA-DRB1*03.