Role of Microglia in Neuropathic Pain.

Microglial cells are specialized macrophage cells of the central nervous system responsible for the innate immunity of the spinal cord and the brain. They protect the brain and spinal cord from invaders, microbes, demyelination, trauma and remove defective cells and neurons. For immune protection, microglial cells possess a significant number of receptors and chemical mediators that allow them to communicate rapidly and specifically with all cells of the nervous tissue. The contribution of microglia in neuropathic pain challenges conventional concepts toward neurons being the only structure responsible for the pathophysiological changes that drive neuropathic pain. The present study is a narrative review focusing on the literature concerning the complex interaction between neurons and microglia in the development of neuropathic pain. Injury in the peripheral or central nervous system may result in maladaptive changes in neurons and microglial cells. In neuropathic pain, microglial cells have an important role in initiating and maintenance of pain and inflammation. The interaction between neural and microglial cells has been proven extremely crucial for chronic pain. The study of individual mechanisms at the level of the spinal cord and the brain is an interesting and groundbreaking research challenge. Elucidation of the mechanisms by which neurons and immune cells interact, could constitute microglial cells a new therapeutic target for the treatment of neuropathic pain.

Acupuncture-induced haemothorax: a rare iatrogenic complication of acupuncture.

This paper reports a rare iatrogenic complication of acupuncture-induced haemothorax and comments on the importance and need for special education of physicians and physiotherapists in order to apply safe and effective acupuncture treatment. A 37-year-old healthy woman had a session of acupuncture treatments for neck and right upper thoracic non-specific musculoskeletal pain, after which she gradually developed dyspnoea and chest discomfort. After some delay while trying other treatment, she was eventually transferred to the emergency department where a chest X-ray revealed a right pneumothorax and fluid collection. She was admitted to hospital and a chest tube inserted into the right hemithorax (under ultrasound guidance) drained 800 mL of bloody fluid (haematocrit (Hct) 17.8%) in 24 h and 1200 mL over the following 3 days. Her blood Hct fell from 39.0% to 30.8% and haemoglobin from 12.7 to 10.3 g/dL. The patient recovered completely and was discharged after 9 days of hospitalisation. When dyspnoea, chest pain and discomfort occur during or after an acupuncture treatment, the possibility of secondary (traumatic) pneumo- or haemopneumothorax should be considered and the patient should remain under careful observation (watchful waiting) for at least 48 h. To maximise the safety of acupuncture, specific training should be given for the safe use of acupuncture points of the anterior and posterior thoracic wall using dry needling, trigger point acupuncture or other advanced acupuncture techniques.