Common Viral Infection 1 - Level 4, Semester 8 PDF

Level 4 Semester 8 Module (CWH2) Common viral infection 1 Prof. Eman mahmoud INSTRUCTOR INFORMATION Contact: Dr. Eman Mahmoud Ibrahiem Department: Pediatrics Official email: [email protected] Mobile (optional): Academic hours: Sa...

Level 4 Semester 8 Module (CWH2) Common viral infection 1 Prof. Eman mahmoud INSTRUCTOR INFORMATION Contact: Dr. Eman Mahmoud Ibrahiem Department: Pediatrics Official email: [email protected] Mobile (optional): Academic hours: Saturday: 10:12 AM Monday : 10:12 AM Prof. Eman mahmoud  ‫‪Mission and Vision of Faculty‬‬ ‫رسالة الكلية‪:‬‬ ‫تلتزم كلية الطب البشري – جامعة الدلتا للعلوم والتكنولوجيا بتقدیم برنامج تعليمي تكاملي متميز یقووم علو المـورار‬ ‫والمعرفرة ویـردف ال تخریج أطبراء قرادرین عل الوفراء بواجبراتـم المـنيورة واخالققيورةو والتعلويم الطبوي المسوتمر‬ ‫والمشاركة الفعالة في البحث العلمي والدمة المجتمع‪.‬‬ ‫رؤیة الكلية‪:‬‬ ‫تسعى كلیة الطب البشري ‪ -‬جامعةة الةتلتا للعلةوا والتكوولوجیةا مة طةیق تطبیةج بروةام الةتعلا ال ةا ا لةى اكتسـةـاب‬ ‫الجتارات أ تكو في م تمة المؤسسات الطبیة التعلیمیة المتمیزة لى المستوى المحلي وال ومى والعالمي‪.‬‬ ‫‪Prof. Eman mahmoud‬‬  Learning Outcomes By the end of the lecture, students will be able to: Define Five common childhood exanthems (Measles, German measles, Roseola infantoum, Erythema infectiousm and Chicken box) For each exanthem: Review the epidemiology Describe the clinical picture Identify the diagnosis Enumerate the complications Outline the treatment plan Recognize the prophylaxis Prof. Eman mahmoud  Measles Definition: Measles is an acute highly communicable disease, caused by measles virus. Etiology: Measles virus (rubeola virus): RNA virus. Mode of transmission: Droplet infection, Through the respiratory tract or conjunctivae, Contact with articles freshly soiled by nose and throat secretions of an infected child Face-to-face contact is NOT necessary, because viable virus may be suspended in air for 1 hr. after the patient with the source case leaves a room Prof. Eman mahmoud  Measles Season: The season is commonly during winter and spring. Incubation period: 8-12 days (usually 10 days). Infectivity: The period of infectivity is from the 3 days before until 4-6 days after the onset of rash. Prof. Eman mahmoud  Measles Clinical picture: Age: The highest incidence is 2—14 years. Prodromal (Catarrhal) stage : (5 -7 days) Characterized by its severity (in comparison with German measles). Fever (38.5 - 40°C), highest just before the appearance of the rash. Malaise Manifestations of catarrhal inflammation of all mucous membranes of the body: (Cough (dry irritating, barking in character) –Sneezing- mucopurulent nasal discharge and a sore throat- Lacrimation, photophobia, and non purulent conjunctivitis ) Prof. Eman mahmoud  Measles Enanthem and Koplik’s spots: Koplik’s spots are pathognomonic: It appears 1-4 days before the appearance of the rash. They usually disappear when the skin rash appears. Commonly noted on the buccal mucosa opposite the 2nd molar teeth. They are small grayish white spots (mononuclear cell infiltrates) surrounded by rose red areas. Prof. Eman mahmoud  Measles Exanthem (Eruptive/skin rash) stage: It Appears usually in the 5th day of illness. It begins as a maculopapular rash at the hair line on the forehead, back of neck and behind the ears, It progresses to involve the whole body. The rash is blotchy, irregular and coalesces into large red areas of varying sizes and shapes. The fever remains very high during the appearance of the rash. Generalized lymphoid hyperplasia is usually present Black measles. Rash may be Hemorrhagic in severe cases Prof. Eman mahmoud  Measles Convalescence stage: The rash fades over about 7 days, the rash begins to fade in the same sequence (from the face downwards ) with branny desquamation (except hands and feet) The skin returns to normal, or a light brown pigmentation (post measles stain) is left that may persist for months. The cough lasts the longest, often up to 10 days Prof. Eman mahmoud  Measles Diagnosis: 1- History: 2- Clinical picture: 3- Laboratory findings: CBC : Leucopenia with lymphocytes decreased more than neutrophils Leukocytosis occurs if 2ry bacterial infect. ESR and CRP: Normal Rise of anti-measles antibody titer, IgM Virus isolation : blood, urine and naso- pharyngeal secretions during the infectivity period Prof. Eman mahmoud  Measles Complications: Respiratory complications: Otitis media, Sinusitis, mastoiditis, laryngitis, laryngotracheobronchitis, Bronchopneumonia,… Neurological Complications: Febrile convulsions, Encephalitis: (Direct invasion of the virus, Subacute measles encephalitis: manifests after 1-10 mo in immunocompromised patients, Subacute sclerosing panencephalitis (SSPE), it is a progressive fatal neurological disease, seen mainly After 7-13 yr, due to slow virus infection of the CNS), Aseptic meningitis, Guillain-Barre’ syndrome, Hemiplegia.,………. Prof. Eman mahmoud  Measles Skin and mucous membranes complications: Black measles : Hemorrhagic rash & DIC Purpura : thrombocytopenic and non-thrombocytopenic. Skin infections as impetigo, furunculosis and gangrenous stomatitis (cancrum oris). Digestive tract: Thrush, ulcerative stomatitis, Gastroenteritis, Ulcerative colitis, Mesenteric adenitis. Other less common complications: Cervical lymphadenitis, Mediastinal lymphadenitis, Myocarditis , Corneal ulcers.  Measles Differential Diagnosis: 1. In prodromal stage: Common cold, influenza and catarrhal stage of whooping cough. 2. In the eruptive stage: Other causes of maculopapular rash Prof. Eman mahmoud Treatment: Measles 1. General: supportive Isolation of the patient (for 5-7 days from the onset of the rash). Bed rest until afebrile - Antipyretics for fever- Hygienic care of the eyes and mouth Diet is offered as tolerated by the child- Cough depressants ONLY for dry irritating cough Treatment with oral vitamin A : Reduces the mortality and morbidity Administered once daily for 2 days : 200,000 IU for children ≥12 mo 100,000 IU for infants 6 mo - 11 mo 50,000 IU for infants < 6 mo In children with signs and symptoms of vitamin A deficiency : 3rd dose , 2 - 4 wk. after the 2nd dose. Prof. Eman mahmoud  Measles 2. Specific: NO specific treatment: Antiviral therapy is not effective (Immunocompromised patients, the antiviral drug “Ribavirin” may be used) 3. Treatment of complications: Antibiotics for secondary bacterial infections, Symptomatic treatment for encephalitis as anticonvulsants, Correction of dehydration and electrolytes in diarrhea Prof. Eman mahmoud  Measles Prophylaxis: 1. Active immunization 2. Passive immunization/Postexposure Prophylaxis The vaccine is effective in prevention or modification if given within 72 hr. of exposure. Immune globulin given up to 6 days after exposure to prevent or modify infection. o Immunocompetent children : 0.25 mL/kg IM o Immunocompromised children : 0.5 mL/ kg o Maximum dose in both cases is 15 mL/kg Prof. Eman mahmoud  German Measles (Rubella) (3-day Measles) Definition: It is an acute infectious disease. It is characterized by typical eruption and lymph node enlargement. Etiology: Virus of German measles (rubella virus) RNA virus. Modes of transmission: Droplet infection, Direct contact, Trans-placental congenital infection. Season: Spring. Incubation period: 14 - 21 days. Prof. Eman mahmoud  German Measles Infectivity period: Viral shedding from the nasopharynx begins 10 days after infection and up to 2 wk. from onset of the rash. Period of highest communicability : 5 days before - 6 days after rash appearance. Infant with congenital rubella is infectious for at least 10-12 months. Prof. Eman mahmoud  German measles Clinical picture I. Prodromal stage: Shorter than that of measles (hours up to 1-2 days). May pass unnoticed, Mild fever (not more than 38°C), malaise, anorexia, headache. Mild nasopharyngitis, Red eyes with or without eye pain. No photophobia. II. Enanthem and lymph nodes enlargement: The enanthem appears just before the rash in the form of small rose-colored spots or petechial hemorrhages on the soft palate and hard palate, Lymphadenopathy is the most characteristic sign of the disease. Prof. Eman mahmoud  German measles Lymphadenopathy is the most characteristic sign of the disease: It is evident 24 hours before the rash and present for a ≥ week. The lymph nodes involved are post-auricular, posterior cervical and posterior occipital. The lymph nodes are tender, but the tenderness decreases as the rash appears. Mild splenomegaly and generalized lymphadenopathy may occur III. Exanthem (Skin rash/ Eruptive) stage: On the first day the rash simulates that of measles (discrete maculopapular rash) called morbilliform rash. On the second day, it resembles scarlet fever (finely papular diffuse erythema) called scarlatiniform rash. On the third day, the rash fades with no desquamation or staining 3-day measles. Prof. Eman mahmoud  German Measles Diagnosis: History of exposure: Clinical picture: Laboratory findings: Leukopenia, neutropenia, and mild thrombocytopenia, Rubella Immunoglobulin M (IgM) antibodies are detectable in the first few day illness and in the blood of affected newborn infants, Isolation of the virus from various tissues. Differential Diagnosis: Measles Prof. Eman mahmoud  German Measles Complications: Not common in childhood. Encephalitis : 2 forms: o Post infectious syndrome following acute rubella o Rare progressive panencephalitis manifesting as a neurodegenerative disorder years following rubella. Thrombocytopenic purpura (rare), Myocarditis, Polyarthritis, Congenital rubella syndrome Prof. Eman mahmoud  German Measles Prevention: Active immunization: MMR vaccine Passive immunization: o Immune serum globulin within the 1st week of exposure. o It is given to nonimmune pregnant women on exposure Prof. Eman mahmoud  The Human Herpesviruses There are currently “8” known human herpesviruses 1&2. Herpes simplex virus 1 and 2 3. Varicella zoster virus 4. Cytomegalovirus 5. Epstein-Barr virus 6,7&8. Human herpesviruses 6, 7 and 8 The hallmark of the herpesviruses: After primary infection, latency is established. There is long-term persistence of the virus within the host, usually in a dormant state. After certain stimuli, reactivation of infection may occur. Prof. Eman mahmoud  Roseola Infantum– (Sixth disease) Definition: Exanthem subitum: Means a sudden rash. It is an acute infectious exanthematous disease of infancy Etiology: Roseola is also called sixth disease because the HHV type 6 most often, Less frequently, HHV type 7 Double-stranded DNA viruses Modes of transmission: Droplet infection. Incubation period: 1-2 weeks (10 days) Age: Infants, with highest incidence 6 and 15 months. Prof. Eman mahmoud  Roseola Infantum Infectivity: It is greater during the febrile phase of the disease. I. Prodromal stage: Acute onset with high fever (often > 40° C) Fever persists for 1-5 days with malaise, irritability and even convulsions (febrile convulsions) URT symptoms, nasal congestion, OM, cough, Most children are alert, behave normally The fever drops suddenly The temperature may remain subnormal for few hours during which the rash appears Prof. Eman mahmoud  Roseola Infantum II. Eruptive stage: The rash is pale rosy maculopapular rash, very similar to rubella, Mainly present on the neck and trunk, then spreading to face & extremities, It fades on pressure and is very transient, It appears on 4th day & disappears in 1-2 days, It is non- pruritic, It leaves no desquamation or pigmentation. N.B.: The appearance of the rash after disappearance of the temperature is simulated by the rainbow that follows a storm. In measles and germen measles, the rash spreads down wards: face → trunk→ limbs, But in Roseola, the rash, 1st on trunk → periphery. Prof. Eman mahmoud Roseola infantum Erythematous, blanching macules and papules  Roseola Infantum Laboratory findings: Leukocytosis in the first two days. Leukopenia as low as 3,000/mm3 and definite lymphocytosis (90%) starting from the third day. Differential Diagnosis: Other exanthematous diseases. Complications: None Encephalopathy is rare Treatment: 1- General: Rest, antipyretics and cold compressors to control the high grade fever. Anticonvulsants if convulsions occur. 2- Specific: Non. Prophylaxis: Not known. Prof. Eman mahmoud  Erythema Infectiosum- Fifth disease Definition: Fifth disease because it was fifth in a list of historical classifications of common skin rash illnesses in children. Etiology: Parvovirus B 19, a single-stranded DNA virus Modes of transmission: Droplet infection. Incubation period : 7-14 days (1 week). Infectivity: Children with rash are not infectious. Isolation is not indicated EXCEPT in patients with aplastic anemia Prof. Eman mahmoud  Erythema Infectiosum- Fifth disease Clinical picture: Age: School age (5-15 years). NO fever, NO prodromal stage. The first symptom is the rash which progresses as follows: o The rash appears first on the cheeks as very red macules which are warmed slightly raised o Slapped cheek appearance. There is circumoral pallor Skin rash: o After 4 days, the previous rash disappears AND maculopapular rash appears on the shoulders and extensor surfaces of the extremities. Prof. Eman mahmoud  Erythema Infectiosum- Fifth disease In 3 days, it extends to involve the flexor surfaces and trunk. The rash fades by central clearing, giving a typical lace-like pattern of geographic lines or reticulated appearance. Palms and soles are rarely involved. The rash is pruritic and resolves without desquamation. This rash lasts 2-40 (average 10-12) days. Rash tends to recur with exercise warm , rubbing of the skin, exposure to sunlight or extremes or heat and cold or emotional upsets. Laboratory findings: Reticulocytopenia lasting 7 to 10 days, mild anemia, thrombocytopenia, lymphopenia, and neutropenia Prof. Eman mahmoud Erythema infectiosum. Erythema of the bilateral cheeks, which has been likened to a “slapped cheek” appearance Erythema infectiosum. Reticulate erythema on the upper arm  Erythema Infectiosum- Fifth disease Differential Diagnosis Measles , rubella, infectious mononucleosis, Drug eruptions, Lupus erythematosus, Scarlet fever Complications: Arthritis - Aplastic crises in patients with chronic hemolytic anemias as sickle cell anemia, Encephalopathy, aseptic meningitis & Pneumonia (rare).. Treatment: No specific treatment. Prof. Eman mahmoud  Chickenpox Definition: It is an acute highly contagious exanthematous disease of infancy and childhood Etiology: Varicella-Zoster virus, double-stranded DNA virus Mode of infection: Droplet infection /Air-borne infection. Direct contact with vesicles (crusts are not infectious). Incubation Period: 2 - 3 weeks (usually 15 days) Infectivity period: 24h before rash, till all lesions are crusted, usually 6-8 days after eruption. Prof. Eman mahmoud  Chickenpox Clinical Picture: Age: Any age (even the newborn), more common at 2-8 years I. Prodromal stage: It is very mild and very short. The disease begins with low grade fever, malaise and anorexia for about 24hs before rash. II. Eruptive (skin rash) stage: The rash is characterized by being: 1. Centripetal: i.e., heaviest on the trunk especially the back. 2. Rapid evolution of the rash from papule to vesicle and lastly crust. Prof. Eman mahmoud  Chickenpox 3. Polymorphic: i.e., the presence of lesions in all states in any one anatomical area. 4. Rash continue to erupt for 3-4 days. 5. Pruritus (itching) is a constant and alloying character of the rash. 6. The lesions are superficial, and no scar tissue is formed on healing. 7. Pustular stage is not a constant stage (except if secondary infection occurs). 8. Hemorrhage may rarely occur in the vesicles (hemorrhagic varicella). 9. The rash disappears in 10-14 days (crusts are not infectious). Mild generalized lymphadenopathy is present. N.B.: The disease is generally mild in children, but more severe in neonates, adults, and immunosuppressed individuals Prof. Eman mahmoud  Chickenpox Vesicles also develop on mucous membranes o Mouth o Commonly on the hard palate and usually rupture so rapidly o They appear as small shallow ulcers. o The palpebral conjunctiva, pharynx, larynx, trachea, and rectal & vaginal mucosa may be involved. Laboratory Findings: Leucopenia, but lymphocytosis occurs later on, Virus can be isolated by scraping the floor of fresh vesicles. Differential Diagnosis: From other causes of papulo-vesicular rash Prof. Eman mahmoud  Chickenpox Complications: 1. Secondary bacterial infection of the skin lesions: It is the most common, by streptococci or staphylococci 2. Respiratory complications: Pneumonia due to viral invasion (Varicella pneumonia) or 2ry bacterial infection, Laryngeal edema. 3. Neurological complications: Viral encephalitis & aseptic meningitis syndrome, Cerebellar Ataxia, Guillain-Barre syndrome, transverse myelitis, facial nerve palsy,…….. 4. Keratitis and corneal ulceration, which may be dangerous to vision. Prof. Eman mahmoud  Chickenpox 4. Carditis: Myocarditis, pericarditis, and endocarditis. 5. Hepatitis & Reye syndrome 6. Arthritis and acute myositis of the limb muscles. 7. Hematologic complications: Thrombocytopenia, purpura fulminant and DIC Progressive varicella: Occurs in immuno-deficient patients or patients with neoplastic disease or patients on steroids. Congenital varicella: Early infection in the pregnant woman may result in fetal varicella infection. Low birth weight, cortical atrophy, seizures, mental retardation, microcephaly & scarring of the skin. Mortality rate is high Prof. Eman mahmoud  Chickenpox Treatment I. General: Antipyretics e.g., paracetamol. Aspirin should be avoided, Local calamine lotion and antihistaminic drugs to relieve itching, Keep fingernails cut short, Mouth hygiene in case of mouth lesions. II. Specific TTT Not recommended in uncomplicated cases. Antiviral drugs e.g., acyclovir (Zovirax) : severe conditions and in immunocompromised patients. III. TTT of complications: Local or systemic antibiotics for 2ry bacterial infection. Supportive treatment for encephalitis,… Prof. Eman mahmoud  Chickenpox Prevention: 1- Active immunization: 2- Passive immunization: Using Zoster Immuno-Globulin (ZIG), or Varicella-zoster immunoglobulin (VZIG) IM of 5 ml of within 72 hrs. after exposure is used for immunosuppressed children. Prof. Eman mahmoud  Herpes Zoster( Shingles) Latent varicella zoster can reactivate, causing a vesicular eruption in the distribution of sensory nerves It occurs most commonly in the thoracic region, although any dermatome can be affected Recurrent HZ may be a manifestation of underlying immune suppression, e.g., HIV infection. Prof. Eman mahmoud Learning Resources: Illustrated Textbook of Paediatrics,6Ed.2022 ▪ Nelson Essentials of Pediatrics 8th Edition, Karen Marcdante & Robert M. Kliegman. Elsevier (2023) ▪ https://my.clevelandclinic.org/health/diseases/22510-viral-exanthem-rash ▪ https://www.seattlechildrens.org/conditions/a-z/rash-or-redness- widespread/ ▪ https://www.health.com/viral-rash-7629239 ▪ https://www.clinikally.com/blogs/news/viral-rashes-uncovered-identifying- and-managing-skin-reactions-in-adults-and-kids ▪ https://reference.medscape.com/slideshow/skin-rashes-6004772