Garcia-Lara - UM2010 - Microbiol. - Tularemia & Lyme Disease 2024-2025 PDF

Dr Jorge Garcia-Lara MICROBIOLOGY Unit: ISCM Module: UM2010 Yr. 2024-2025 Tularemia by : LECTURE 1 CORE Dr. GARCIA-LARA Bitesize 7...

Dr Jorge Garcia-Lara MICROBIOLOGY Unit: ISCM Module: UM2010 Yr. 2024-2025 Tularemia by : LECTURE 1 CORE Dr. GARCIA-LARA Bitesize 7 SLIDES School of Medicine Medicinae Baccalaureus Baccalaureaus Chirurgiae (MBBS) Physician Associate Studies (MPAS) 1  Dr Jorge Garcia-Lara Oyston et al. 2004.. TULARAEMIA: BIOTERRORISM DEFENCE RENEWS INTEREST IN FRANCISELLA TULARENSIS. Nature Reviews Microbiology. 967 School of Medicine Medicinae Baccalaureus Baccalaureaus Chirurgiae (MBBS) Physician Associate Studies (MPAS) 2  Dr Jorge Garcia-Lara Tularemia acute, febrile, granulomatous, Francisella tularensis (Gram-, aerobic) infectious zoonosis caused by rabbits, ticks present in soil, mud and water samples, carcasses atypical pneumonia; inhalation pneumonia 3  Dr Jorge Garcia-Lara What is an atypical pneumonia ? not caused by common pathogens not purely lobar pneumonia – instead restricted to small regions more atypical generalized symptoms: fever, headache, myalgia, bronchopneumonia often irresponsive to common antibiotics restricted sputum patient looks better than what one would expect from the symptoms diagnosis typically and generally not culture- based School of Medicine Medicinae Baccalaureus Baccalaureaus Chirurgiae (MBBS) Physician Associate Studies (MPAS) 4  Dr Jorge Garcia-Lara Diagnosis in atypical pneumonia ? typically immunological determination (liver, spleen, bone marrow, lung or kidney) PCR, from primary ulcer swabs in ulceroglandular tularemia some can be cultured, like Legionella or Francisella direct isolation of Francisella typically NOT performed because of the HAZARDOUS nature fastidious (special medium supplemented with cysteine, blood/haemoglobin in microaerophilic conditions) one of the most infectious bacterial species known leading disseminating infections in humans and other mammalian hosts it is NOT a NOTIFIABLE DISEASE (to Public Health England) 5  Dr Jorge Garcia-Lara General symptoms fever and chills - recurrent headache anorexia malaise and fatigue or prostration myalgias cough vomiting pharyngitis abdominal pain it can also go septic pneumonitis (in some patients) School of Medicine Medicinae Baccalaureus Baccalaureaus Chirurgiae (MBBS) Physician Associate Studies (MPAS) 6  Dr Jorge Garcia-Lara Different presentations of tularemia Ulceroglandular tularemia (SCRATCH OR ABBRASION) painful lymphadenopathy, ulcerated skin lesion Glandular tularemia lymphadenopathy, no cutaneous lesions Oculoglandular tularemia (RUBBING EYE WITH CONTAMINATED FINGER) painful conjunctivitis, lymphadenopathy Oropharyngeal tularemia stomatitis and exudative pharyngitis or tonsillitis; abdominal pain, nausea, and vomiting; cervical lymphadenopathy; diarrhea; gastrointestinal bleeding Intestinal tularemia abdominal pain, vomiting, and diarrhea Pneumonic tularemia (CONTAMINATED AEROSOLS) dry cough, dyspnea, and pleuritic-type chest pain Typhoidal tularemia fever, chills, myalgias, malaise, weight loss (30-60% mortality) [ some visual examples in next page ] 7  Dr Jorge Garcia-Lara Ulceroglandular tularemia Glandular tularemia Oculoglandular tularemia 8 http://emedicine.medscape.com/article/230923-overview  Dr Jorge Garcia-Lara virulence determined by its ability to evade phagosome/lysosome fusion and then multiply within eukaryotic cell little is known about the pathogenic mechanisms in F. tularensis associated with type VI-like secretion system (most widely spread bacterial secretion machinery - Burkholderia mallei, Vibrio cholerae, Salmonella typhimurium) 9  Dr Jorge Garcia-Lara MICROBIOLOGY Unit: ISCM Module: UM2010 Yr. 2024-2025 Lyme Disease by : LECTURE 1 CORE Dr. GARCIA-LARA Bitesize 8 SLIDES School of Medicine Medicinae Baccalaureus Baccalaureaus Chirurgiae (MBBS) Physician Associate Studies (MPAS) 10 Dr Jorge Garcia-Lara 11  Dr Jorge Garcia-Lara Lyme disease 12  Dr Jorge Garcia-Lara 1st recognized in Lyme, Connecticut (US) Borrelia burgdorferi (spirochete) Lyme disease is a zoonotic disease transmitted by the Blacklegged tick (Ixodes species – mainly Ixodes scapularis or Deer tick) as it often happens with infectious diseases, the diagnosis is greatly influenced by the history of the patient, e.g., travel to endemic areas, identification or recollection of a tick bite, contact with animals or high grass where the ticks like to reside, … serology (ELISA or Western blot) is the laboratory diagnostic tool doxycycline or amoxycillin 13  Dr Jorge Garcia-Lara Wilhelm “Willie” Burgdorfer, 1954 Inoculating Ornithodoros ticks Borrelia burgdorferi 14  Dr Jorge Garcia-Lara “ A vaccine went to the market … … before medical research advanced enough to realize that it led to autoimmune responses” LYMErix, a vaccine produced by GSK against the OspA (Outer surface protein A) of Borrelia burgdorferi the immunodominant epitope of OspA, leads the production of autoantibodies to peptides within the leukocyte integrin LFA-1 and/or other human body targets Nigrovic, L. E., and K. M. Thompson. ‘The Lyme Vaccine: A Cautionary Tale’. Epidemiology and Infection 135, no. 1 (January 2007): 1–8. https://doi.org/10.1017/S0950268806007096. 15  Dr Jorge Garcia-Lara ticks (Ixodes scapularis) can attach to any part of the human body but are often found in hard-to-see areas (e.g., groin, armpits, and scalp) the tick must be attached for 36 hours or more before Borrelia burgdorferi can be transmitted most humans are infected through immature ticks called nymphs (90% of all cases) nymphs are tiny (less than 2 mm) = difficult to see Lyme disease risk is highest in the spring and summer when nymphs are seeking a blood meal. No person to person transmission ! 16 Dr Jorge Garcia-Lara 17  Dr Jorge Garcia-Lara Skin presentation : immediate first symptom after bite (typically) Erythema migrans (bull’s eye rash) typical first presentation (in its centre lies the tick biting site with the tick, a pustule or Erythema (chronicum) migrans a vesicle) second stage presentation following haematogenous spread 18  Dr Jorge Garcia-Lara Skin presentation : immediate first symptom after bite (typically) Erythema migrans (bull’s eye rash) round / oval rash (average 16 cm) pink, red, or purple it expands over days to weeks not itchy, hot or painful usually maybe with a vesicle or pustule in the middle usually visible within 1 to 4 weeks after rash Erythema migrans (bull’s eye rash) is not always present in Lyme disease, sometimes it is purely a large and homogeneous erythema 19  Dr Jorge Garcia-Lara A few considerations in diagnosis Look for the rash/tick in hidden body places, e.g., flexor creases in the body, under breasts, or legs No rash or recollection of bite does not preclude a Lyme disease diagnosis It may be accompanied by flu-like symptoms (geographic variants – more common in US than Europe) Tick bites in general may lead to non-Lyme disease erythema, but typically subside within 48 hours School of Medicine Medicinae Baccalaureus Baccalaureaus Chirurgiae (MBBS) Physician Associate Studies (MPAS) 20  Dr Jorge Garcia-Lara Consider Lyme disease if : or : Cognitive impairment, Eye symptoms — e.g. uveitis or e.g.,memory problems and keratitis difficulty concentrating Inflammatory arthritis in 1 or more Fatigue joints (may be fluctuating) Fever and sweats. Migratory cardiac problems — Headache e.g., heart block or pericarditis. Malaise Neurological symptoms — e.g., facial palsy or other unexplained Migratory joint/muscle cranial nerve palsies, meningitis, aches/pain mononeuritis multiplex or other Neck pain or stiffness unexplained radiculopathy; or rarely Paraesthesia (pins and encephalitis, neuropsychiatric presentations or unexplained white needles) matter changes on brain imaging Swollen glands Skin rashes — such as acrodermatitis chronica atrophicans or lymphocytoma. 21  Dr Jorge Garcia-Lara Late stage Lyme disease Months or years after infection Chronic Lyme arthritis (chronic severe joint pain and swelling) in one or more large joints, mostly the knee (more common in North America than in Europe) Acrodermatitis Chronic neurological disorders e.g., chronica atrophicans shooting pains, confusion, dizziness, short- term memory loss Acrodermatitis chronica atrophicans, almost exclusively in Europe 22  Dr Jorge Garcia-Lara School of Medicine Questions? [email protected] @GarciaLaraClan #UCLanMicrobiology School of Medicine Medicinae Baccalaureus Baccalaureaus Chirurgiae (MBBS) Physician Associate Studies (MPAS) 23