Tears
CDC is collaborating with the Food and Drug Administration (FDA) and state and local health departments to investigate a multistate outbreak of an extensively drug-resistant strain of Pseudomonas aeruginosa. The outbreak strain, carbapenem-resistant Pseudomonas aeruginosa with Verona integron-mediated metallo-β-lactamase and Guiana extended-spectrum-β-lactamase (VIM-GES-CRPA), had never been reported in the United States prior to this outbreak. The outbreak is associated with multiple types of infections, including eye infections. The investigation to date has identified artificial tears as a common exposure for many patients.
tears
Most patients reported using artificial tears. Patients reported over 10 different brands of artificial tears and some patients used multiple brands. EzriCare Artificial Tears, a preservative-free, over-the-counter product packaged in multidose bottles, was the brand most commonly reported. This was the only common artificial tears product identified across the four healthcare facility clusters. Laboratory testing by CDC identified the presence of VIM-GES-CRPA in opened EzriCare bottles from multiple lots; these bottles were collected from patients with and without eye infections and from two states. VIM-GES-CRPA recovered from opened products match the outbreak strain. Testing of unopened bottles of EzriCare Artificial Tears is ongoing to assist in evaluating for whether contamination may have occurred during manufacturing. Patients and healthcare providers should immediately stop the use of EzriCare Artificial Tears pending additional information and guidance from CDC and FDA.
Basal tears are in your eyes all the time to lubricate, nourish and protect your cornea. Basal tears act as a constant shield between the eye and the rest of the world, keeping dirt and debris away.
Reflex tears are formed when your eyes need to wash away harmful irritants, such as smoke, foreign bodies or onion fumes. Your eyes release them in larger amounts than basal tears, and they may contain more antibodies to help fight bacteria.
Emotional tears are produced in response to joy, sadness, fear and other emotional states. Some scientists have proposed that emotional tears contain additional hormones and proteins not present in basal or reflex tears.
Lacrimal glands above each eye produce your tears. As you blink, tears spread across the surface of the eye. Then the tears drain into puncta, tiny holes in the corners of your upper and lower eyelids. Your tears then travel through small canals in the lids and down a duct before emptying into your nose. There, tears will either evaporate or be reabsorbed.
SummaryThe Centers for Disease Control and Prevention (CDC) is issuing this Health Alert Network (HAN) Health Advisory about infections with an extensively drug-resistant strain of Verona Integron-mediated Metallo-β-lactamase (VIM) and Guiana-Extended Spectrum-β-Lactamase (GES)-producing carbapenem-resistant Pseudomonas aeruginosa (VIM-GES-CRPA) in 12 states. Most patients reported using artificial tears. Patients reported more than 10 different brands of artificial tears, and some patients used multiple brands. The majority of patients who used artificial tears reported using EzriCare Artificial Tears, a preservative-free, over-the-counter product packaged in multidose bottles. CDC laboratory testing identified the presence of the outbreak strain in opened EzriCare bottles with different lot numbers collected from two states. Patients and healthcare providers should immediately discontinue using EzriCare artificial tears pending additional guidance from CDC and the Food and Drug Administration (FDA).
Review of common exposures revealed that most patients, including most patients with eye infections, used artificial tears prior to identification of VIM-GES-CRPA infection or colonization. Patients reported more than 10 brands of artificial tears, and some patients used multiple brands. The majority of patients who used artificial tears reported using EzriCare Artificial Tears, a preservative-free product dispensed in multidose bottles. This was the only common artificial tears product identified across the four healthcare facility clusters. CDC laboratory testing identified the presence of VIM-GES-CRPA in opened EzriCare Artificial Tears bottles from multiple lots; these bottles were collected from patients with and without eye infections in two states. These product-related VIM-GES-CRPA match the outbreak strain. VIM-GES-CRPA recovered from opened bottles could represent either bacterial contamination during use or during the manufacturing process. Testing of unopened bottles of EzriCare Artificial Tears is ongoing to assist in evaluating for whether contamination may have occurred during manufacturing.
The functions of tears include lubricating the eyes (basal tears), removing irritants (reflex tears), and also aiding the immune system.[3] Tears also occur as a part of the body's natural pain response.[4] Emotional secretion of tears may serve a biological function by excreting stress-inducing hormones built up through times of emotional distress.[5][6] Tears have symbolic significance among humans.[4]
Tears are made up of three layers: lipid, aqueous, and mucous.[7] Tears are composed of water, salts, antibodies, and lysozymes (antibacterial enzymes); though composition varies among different tear types. The composition of tears caused by an emotional reactions differs from that of tears as a reaction to irritants, such as onion fumes, dust, or allergens. Emotional tears contain higher concentrations of stress hormones such as adrenocorticotropic hormone and leucine enkephalin (a natural pain killer), which suggests that emotional tears play a biological role in balancing stress hormone levels.[8]
The lacrimal glands secrete lacrimal fluid, which flows through the main excretory ducts into the space between the eyeball and the lids.[10] When the eyes blink, the lacrimal fluid is spread across the surface of the eye.[10] Lacrimal fluid gathers in the lacrimal lake which is found in the medial part of the eye. The lacrimal papilla is an elevation in the inner side of the eyelid, at the edge of the lacrimal lake.[10] The lacrimal canaliculi open into the papilla.[10] The opening of each canaliculus is the lacrimal punctum. From the punctum, tears will enter the lacrimal sac,[2] then on to the nasolacrimal duct, and finally into the nasal cavity.[10] An excess of tears, as caused by strong emotion, can cause the nose to run. Quality of vision is affected by the stability of the tear film.[11]
The trigeminal V1 (fifth cranial) nerve bears the sensory pathway of the tear reflexes. When the trigeminal nerve is cut, tears from reflexes will stop, while emotional tears will not. The great (superficial) petrosal nerve from cranial nerve VII provides autonomic innervation to the lacrimal gland.[16] It is responsible for the production of much of the aqueous portion of the tear film.
In nearly all human cultures, crying is associated with tears trickling down the cheeks and accompanied by characteristic sobbing sounds. Emotional triggers are most often sadness and grief, but crying can also be triggered by anger, happiness, fear, laughter or humor, frustration, remorse, or other strong, intense emotions. Crying is often associated with babies and children. Some cultures[which?] consider crying to be undignified and infantile, casting aspersions on those who cry publicly, except if it is due to the death of a close friend or relative. In most Western cultures, it is more socially acceptable for women and children to cry than men, reflecting masculine sex-role stereotypes.[17] In some[which?] Latin regions, crying among men is more acceptable.[18][19][20] There is evidence for an interpersonal function of crying as tears express a need for help and foster willingness to help in an observer.[17]
Some modern psychotherapy movements such as Re-evaluation Counseling encourage crying as beneficial to health and mental well-being.[21] An insincere display of grief or dishonest remorse is sometimes called crocodile tears in reference to an Ancient Greek anecdote that crocodiles would pretend to weep while luring or devouring their prey.[22] In addition, "crocodile tears syndrome" is a colloquialism for Bogorad's syndrome, an uncommon consequence of recovery from Bell's palsy in which faulty regeneration of the facial nerve causes people to shed tears while eating.[23][24]
Bogorad's syndrome, also known as "Crocodile Tears Syndrome", is an uncommon consequence of nerve regeneration subsequent to Bell's palsy or other damage to the facial nerve. Efferent fibers from the superior salivary nucleus become improperly connected to nerve axons projecting to the lacrimal glands, causing one to shed tears (lacrimate) on the side of the palsy during salivation while smelling foods or eating. It is presumed[by whom?] that this would cause salivation while crying due to the inverse improper connection of the lacrimal nucleus to the salivary glands, but this would be less noticeable.[23][24] The condition was first described in 1926 by its namesake, Russian neuropathologist F. A. Bogorad, in an article titled "Syndrome of the Crocodile Tears" (alternatively, "The Symptom of the Crocodile Tears") that argued the tears were caused by the act of salivation.[25][26]
Keratoconjunctivitis sicca, known in the vernacular as dry eye, is a very common disorder of the tear film. Despite the eyes being dry, those affected can still experience watering of the eyes, which is, in fact, a response to irritation caused by the original tear film deficiency. Lack of Meibomian gland secretion can mean that the tears are not enveloped in a hydrophobic film coat, leading to tears spilling onto the face.
You may only think of tears as those salty drops that fall from your eyes when you cry. Actually, your tears clean your eyes every time you blink. Tears also keep your eyes moist, which is important for your vision. 041b061a72