Three fears (water sound, light, wind) phenomenon

• Introduction
• Cause
• Examine
• Diagnosis

Introduction

Introduction The phenomenon of "three fears" (water sound, light, wind) is a characteristic symptom of rabies. The incubation period of rabies varies, most of them are within 3 months, and the domestic report averages 66.9 days. The incubation period of 4% to 10% of patients exceeds half a year, 1% exceeds 1 year, and the longest case in the literature is 19 years. The length of the incubation period and the age (small children), the wound site (early onset of head and face bites, an average of 39 days, the average latency of lower limb bites is 90 days), the depth of the wound (short latency is deep), the number of invading viruses and Virulence (small virulence is short) and other factors, such as incomplete expansion, trauma, cold, overwork, etc., can cause disease to occur in advance.

Cause

Cause

Rabies virus has a strong affinity for nerve tissue, mainly through nerve retrograde, centripetal to the central transmission, generally does not enter the blood.

The pathogenesis of rabies can be divided into the following three stages:

1. Extraneural small-volume breeding period: After the virus invades the skin or mucosa from the bite site, it firstly multiplies in the striated muscle cells of the local wound, and invades nearby peripheral nerves by binding to the acetylcholine receptor of the neuromuscular junction. From local wounds to invasive peripheral nerves are not shorter than 72h.

2. Invading the central nervous system from peripheral nerves: The virus spreads to the heart along the axis of the peripheral nerve, and its velocity is about 5 cm/d. After reaching the dorsal root ganglia, it begins to multiply and then invades the spinal cord, which then spreads throughout the central nervous system. Mainly invade neurons in the brain stem and cerebellum. However, it can also be terminated in a certain part during the diffusion process to form a special clinical manifestation.

3. The period from the central nervous system to the various organs: the virus spreads eccentrically from the central nervous system to the peripheral nerves, invading tissues and organs, especially the parotid gland, tongue taste buds, and olfactory nerve epithelium. Due to the damage of the vagus nerve nucleus, swallowing nerve nucleus and hypoglossal nucleus, respiratory muscles and swallowing tendon can occur. Clinically, patients have symptoms such as water-induced dyspnea, difficulty in breathing, and difficulty in swallowing. The sympathetic nerve is stimulated to secrete saliva. Increased sweat; vagus ganglia, sympathetic ganglia and damage to the heart ganglion can cause cardiovascular system dysfunction and even sudden death.

Examine

an examination

Related inspection

Urine routine blood routine

Blood, urine routine and cerebrospinal fluid

The total number of peripheral white blood cells varies from 12,000 to 30000/mm ³ , and neutrophils generally account for more than 80%. Regular urine examination revealed mild proteinuria, occasionally a transparent cast. Cerebrospinal fluid pressure can be slightly increased, the number of cells is slightly increased, generally not more than 200/mm ³ , mainly lymphocytes, protein increased, up to 200mg / d, sugar and chloride normal.

Immunological test

Serum neutralizing antibodies were measured on the 6th day after the disease. On the 8th day after the disease, 50% of the sera were positive, and all were positive on the 15th. After vaccination, neutralizing antibodies are mostly <10 IU, and clinical patients can reach 640 IU.

Virus isolation

There are two ways of biopsy and autopsy. The former can isolate the virus from salivary glands, brain biopsy, cerebrospinal fluid and urine sediment, and the brain tissue has the highest positive rate. At the time of autopsy, the bite local, pericardium, adrenal gland, pancreas, liver, etc. can be positively cultured.

Animal inoculation and internal corpuscle examination

After the death, 10% brain tissue suspension was inoculated into the brain of 2 to 3 weeks old suckling mice. The positive mice showed tremor, vertical hair, tail stiffness, paralysis and other phenomena within 6-8 days, 10-15 The day died due to exhaustion. The inner base corpuscle can be found in the mouse brain.

The dead brain tissue or biting animal brain tissue was used for pathological sectioning or tableting, and the inner kiln body was examined by Seller staining and direct immunofluorescence, and the positive rate was about 70%.

Diagnosis

Differential diagnosis

Rabies need to be differentiated from tetanus, viral meningoencephalitis, and polio. The latent period of tetanus is short, with closed jaws and angulation and no signs of water scarring. Poliomyelitis has no symptoms of water scarring, muscle pain is more common, and other symptoms are mostly resolved. Viral meningoencephalitis has severe changes in consciousness and meningeal irritation, cerebrospinal fluid findings, immunological tests and virus isolation are all helpful in identification.

Patients with rabies-like rickets have a tight throat sensation after an animal bite, and cannot drink water and excitement, but they are not afraid of wind, runny, fever and phlegm. After suggestion, persuasion, and symptomatic treatment, they can often recover quickly.

After vaccination with rabies, fever, joint pain, limb numbness, movement disorders, various spasms, etc. may occur, and it is difficult to distinguish from this type of sputum. However, the former is stopped after vaccination, and most of them are recovered after taking adrenal cortex hormone. Death cases must be confirmed by immunofluorescence test or kinett examination in brain tissue.

Early misdiagnosis, children and bite history is not clear. Patients who have been in the attack stage, according to the dog or cat bite history, biting animals have been identified rabies, and prominent clinical manifestations, such as abnormal feelings in the bite, excitement, fear of the wind, throat, phlegm, runny Khan, all kinds of sputum, etc., can make a diagnosis. If the immunofluorescence test is positive, the diagnosis is unambiguous, and if necessary, a brain corpuscle examination or an animal test is performed in the brain tissue.