Pedia 2.1a Bacterial Infections - Dra Carlos

2.1 Bacterial Infections

Pediatrics II

Dra. Carlos | Date July 25 2014 2014 PEDIATRIC INFECTIOUS DISEASES HIGHLIGHTS A.

Plague  Caused by gram negative coccobacillus Yersinia pestis  Usually through bite of an infected rodent flea  Less common exposures include handling of infected animal tissues, inhalation of infectious droplets from infected animals and direct contact  Endemic in rural areas in central and southern Africa, central Asia and the Indian subcontinent, the northeastern part of South America, and parts of the southwestern United States.  Best known for the “Black Death” which killed millions in Europe during the Middle Ages  July 2014 Yumen, China – 30,000 people locked down and 151 placed in quarantine after the death of a 38 year old victim  Incubation period: 1-6 days. S/Sx of 3 clinical presentations: Bubonic (most common) – rapid onset of fever; bubo (rapid onset, extremely tender, swollen painful lymph gland) usually inguinal Pneumonic (most serious) – high fever, pneumonia, bloody sputum, chills Septicemic – fever, prostration, hemorrhage, thrombocytopenia, acral gangrene  Y. pestis can be isolated from bubo aspirates, blood cultures, or sputum culture if pneumonic. With Waysons stain: bipolar “safety pin” appearance. Serologic test: F1 antigen. st  1 line treatment: Parenteral Streptomycin  Alternate: IV Gentamicin; Oral Doxycycline Typical Scenario A 17 year old boy who has been camping in Africa complains of fever and swelling in his groin area. PE shows an enlarged, tender inguinal lymph node and signs of flea bites on his legs and feet. There are no penile lesions or discharge. Culture of isolates reveals growing gram-negative rods with a safety pin appearance.

B. MERS-CoV (Middle East Respiratory Syndrome – Corona Virus)  Caused by coronavirus called MERS-CoV  Spread by close person-to-person contact  Transmitted by respiratory droplet spread, fomites with droplets and airborne spread  Incubation period: 2-14 days. S/Sx: viral prodrome - high fever, chills, headache, feeling of discomfort and body aches which progresses to severe acure respiratory illness - dry nonproductive cough, shortness of breath, hypoxia nd  2 most common cause of respiratory viral infections, next to rhinovirus  First identified in the Arabian Peninsula from a 60 year old man who died of severe pneumonia and renal failure  Have been found in camels  Proposed explanation: increased mixing between different animal species and humans, climate change, intense international travel, expansion of the immune suppressed population, and changes in the virus itself to adapt to other species.  PCR tests with respiratory samples and serology testing using blood samples is used for identification of MERS-CoV  No specific antiviral treatment  No vaccine to prevent infection Typical Scenario A patient develops fever, cough and shortness of breath within 14 days of being in Saudi Arabia.

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C. Vaccine Preventable Diseases Measles  Goal: eradication. At 9 mos, the cohort is set at 95%. At 15 mos, cohort for MMR is also set at 95%. The Philippines is only at 88% leaving a 7% gap in our population.  Routine immunization of measles is at 9 mos. Vaccine efficacy at 6 mos is 50%, at 9 mos is 85 % while at 1 year old is 95 %. However, we cannot delay giving the vaccine at 1 year old because the attack rate of the measles virus is higher when the child is less than a year old.  Pneumonia – complication of measles which is the most common cause of death in young children  Subacute Sclerosing Panencephalitis (SSPE) – rare postinfectious neurologic complication of measles characterized by regressive changes in intellect and personality. Within months, psychologic symptoms are compounded by neurologic ones – myoclonic jerks, mental and motor deterioration culminating in extreme neurologic dysfunction and death. Pertussis  No pertussis-only vaccine is available. It is available as DTaP.  Waning immunity - getting sick with pertussis or getting pertussis vaccines doesn't provide lifelong protection  Booster: DTaP Poliomyelitis  Philippines is a Polio-free country but an evidence below 10% is needed to maintain our polio free status.  Regular submission of 2 stool samples with an interval of 2 weeks after the onset for all patients ages 0-15 years old who present with weakness, regardless of the cause.

LEADING CAUSE OF MORTALITY WORLDWIDE UNDER 5 YEARS OLD

Figure 1. Distribution of causes of mortality in childern under 5yo.

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Under 5 years old Mortality (infant and neonatal) is a good indicator of the health system of the country. Infant and neonatal mortalities are the most numerous and major cause of mortalities. These are tied up with maternal health. Pneumonia is the major cause of deaths globally which is vaccine preventable. By 2015, the Millennium Developmental Goal 4 is to reduce Under 5 Mortality to 18,000. According to the National Statistical Board, the Philippines is on track from the baseline of 57,000 (1990) to 25,000 (2008). However, MDG has been extended to 2020. Page 1 of 4

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LEADING CAUSES OF VACCINE PREVENTABLE DISEASES WORLDWIDE (2004) 1. 2. 3. 4. 5. 6.

Pneumococcal diseases Diarrhea (rotavirus) Measles Haemophilus influenza type B Pertussis Tetanus (neonatal and non-neonatal)  13 Filipino children die every year due to diarrhea

TOP 10 CAUSES OF DEATHS IN THE PHILIPPINES FOR ALL AGE GROUPS (2009) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

Diseases of the heart Cerebro-vascular diseases Malignant neoplasm Pneumonia Tuberculosis COPD Diabetes Nephritis/Nephrotic syndrome Assault Perinatal conditions  Pneumonia and tuberculosis are the top infections that can cause death. The rest are secondary to lifestyle.

TOP 10 CAUSES OF ILLNESSES IN THE PHILIPPINES FOR ALL AGE GROUPS (2010) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

ACUTE RESPIRATORY INFECTION ACUTE LOWER RESPIRATORY INFECTION AND PNEUMONIA BRONCHITIS Hypertension ACUTE WATERY DIARRHEA INFLUENZA UTI TB Accidents Injuries  7 out of 10 are caused by infectious diseases.  S. pnemoniae is your gram (+) diplococci with a very thick capsule and this is the one that renders the organism virulent. Its thick capsule resists phagocytosis.

IMCI GENERAL DANGER SIGNS IMCI = Integrated Management of Childhood Illnesses

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Is the child able to feed, drink or breastfeed? Does the child vomit everything? Does the child have convulsions during the present illness or has convulsions now? Is the child lethargic or unconscious?  A child with a general danger sign has a serious problem. URGENT referral to a hospital!!!  Upon initial meeting of the baby, one can already check his demeanor and ability to ambulate.

ASSESS MAIN SYMPTOM      

Cough or difficulty of breathing - check Respiratory Rate for a full 1 minute Diarrhea - usually caused by enteric virus such as rotavirus Ear problem/discharge Undernutrition and anemia - check for pallor of conjuctiva and palms Convulsions - meningeal irritation, meningitis, encephalitis Check immunization status

Assess other problems.  This is a good opportunity to remind the parents to update immunizations and to assess for anemia and undernutrition.  When immunization targets fall short, ‘at risk’ population increases and accumulates. When someone or a few acquire the disease, it can affect a whole lot of people causing an outbreak.  When patients are seen in the ER, they are required to follow up the next day at the OPD for completion of missed –out data, to chek if diagnosis was right or if the patient needs to be admitted.

THE CHILD WITH FEVER In children 4 weeks to 5 years, body temperature should be measured using either:  rectal thermometer  electronic thermometer in the axilla  infrared tympanic thermometer (best > 3 months) Fever Requiring Tests Temp > 38C in infants < 3 months Temp ≥ 39C in infants > 3 months Fever is a very important symptom for a child.  usually admitted due to fever  common causes of absenteeism: fever, cough, diarrhea If a patient < 3 months old comes with fever, it is considered severe.  < 3 months is near the neonatal period (some would even say that 3 months is extended neonatal period)  neonates and patients until 3 months old have the same pathogens.  age when etiologic agents change (remember that etiologic agents can be based on age) Neonates have an immature thermoregulatory center.  Even if a neonate doesn’t present with fever, it doesn’t mean that he is well. There are times when the patient is seriously ill but has no fever  immune system if the patient has not been fully developed yet.  Infants < 3 months with fever who appear generally well; who have been previously healthy; who have no evidence of skin, soft tissue, bone, joint, or ear infection; and who have a total white blood cell (WBC) count of 5,000-15,000 cells/μL, an absolute band count of less than 1,500 cells/μL, and normal urinalysis results are unlikely to have a serious bacterial infection.  Mothers tend to bring their child early but if you know the family of the patient and you examine him from time to time, you may opt not to require tests.  Body Temperature  regulated by thermosensitive neurons located in the preoptic or anterior hypothalamus that respond to changes in blood temperature as well as to direct neural connections with cold and warm receptors located in skin and muscle.  Diurnal Circadian Temperature Rhythm – lower body temperatures in the early morning and temperatures approximately 1°C higher in the late afternoon or early evening.  Fever  defined as rectal temperature of ≥38C  a controlled increase in body temperature over the normal values  Hyperpyrexia – temperature of ≥40 C  Fever patterns per se are NOT often helpful in determining a specific diagnosis but observing the clinical characteristics of fever can provide useful information. Page 2 of 4

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Single isolated fever spike is not associated with an infectious disease. May be due to the following:  infusion of blood products  drugs procedures  manipulation of a catheter on a colonized or infected body surface Temperatures in excess of 41°C are most often associated with a non-infectious cause. Causes of very high temperatures (>41°C) include:  central fever (CNS dysfunction)  malignant hyperthermia  malignant neuroleptic syndrome o drug fever heat stroke Temperatures that are lower than normal ( 3 sec -Fever > 5 days -Swelling of limb or joint -Non-weight bearing or not using an extremity -A new lump > 2cm

-Grunting -Severe distress Reduced turgor

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Color: Pallor (reported by parents/ caregivers) Activity: Decreased activity Breathing: signs of respiratory distress  chest retractions (subcostal, intercostal, suprasternal), nasal flaring Hydration: o Signs of dehydration (sunken eyes, decreased capillary refil time, poor skin turgor, depressed fontanelles, dry mucosa, decreased tear production. o Poor feeding o Decreased urine output (Ask for LAST URINE VOIDING) o Capillary refill > 3 seconds Others: Fever >/= 5 days, swelling of limb or joint, non- weight bearing or not using an extremity, a new lump >/= 2cm If intermediate to high risk, may warrant hospital admission

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C. HIGH RISK OF SERIOUS ILLNESS  

Color: Pale, mottled, ashen, blue Activity: Unresponsive, appears ill, and barely rousable; weak high pitched or continuous cry Breathing: Grunting, severe distress Hydration: Reduced skin turgor Others: Non-blanching rash (= glass tumbler test), fever at time of examination, bulging fontanelle, neck stiffness, seizures or focal neurologic bnormality, bilious vomiting (green from bile, there is an obstruction prior to ampula of Vater) Management may have to be started at the ER

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FEVER MANAGEMENT  

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Know the causative agent! Bacteremia would present with non-specific manifestation (ex. fever) versus sepsis which would present with clinical manifestations. Don’t miss possible viral exantems. Non-blanching rash - a rash that doesn’t disappear when pressing a glass. (+) glass tumbler test. Blood: CBC, CRP, ESR, blood culture Urine: Urinalysis, urine culture CSF: Analysis, culture Chest X-ray: if with pulmonary s/sx or high WBC

-Nonblanching rash -Fever at time of examination -Bulging fontanelle -Neck stiffness -Seizures or focal neurologic abnormality -Bilious vomiting

Color: Normal color of skin, lips and tongue Activity: o Responds normally to caretakers o Is content and smiles o Stays awake or awakens quickly weh aroused o Strong, normal cry Breathing: Regular, unlabored Hydration: Normal Others: well-appearing , no fever at time of examination Management: Home management (give water Paracetamol)

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A. LOW RISK OF SERIOUS ILLNESS

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When there is no apparent source of infection, request for:

Table 1. serious illness risk classification

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B. INTERMEDIATE RISK OF SERIOUS ILLNESS

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Check CBC for the predominant cellular action: is it leukocytosis predominant lymphocytes? Or is it leukocytosis predominant neutrophilic? Is there high stabs? Leukocytopenia? Thrombocytopenia and thrombocytosis can both be associated with infection. CRP (C-Reactive Protein) and ESR (Erythrocyte Sedimentation Rate) are on-specific, acute phare reactants. They are indicative of infection, collagen disease or inflammation. In UTI, presence of gram negative organisms on blood culture can be devastating as it can be associated with shock. A normal urinalysis does not rule out UTI, only culture will do. Meningitis is an emergency in pediatrics. During the first 3 days of life, viral infections can present with leukocytosis (WBC up to 50,000). But after the third day or going to the fourth day, if it is viral, the true picture will show that WBC becomes normal or leukopenic predominantly lymphocytic. If it’s bacterial, WBC will persistently go up. Page 3 of 4

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If it’s serious (especially gram negative infection), it can present with leukopenia because the infection can be inhibitory to your WBC.

 Management CBC with differential WBC count and urinalysis should be part of the initial laboratory evaluation.  ANC < 5,000/μL - evidence against indolent bacterial infection other than typhoid fever.  PMN greater than 10,000/mL or nonsegmented PMN leukocytes > 500/mL - high likelihood of having a severe bacterial infection. Direct examination of the blood smear with Giemsa or Wright stain may reveal organisms of malaria, trypanosomiasis, babesiosis, or relapsing fever. Acute Phase Specific Reactants  ESR > 30mm/hr – indicates inflammation and needs further evaluation for infectious, autoimmune, or malignant diseases.  ESR > 100 mm/hr – suggests tuberculosis, Kawasaki disease, malignancy, or autoimmune disease.  A low ESR does not eliminate the possibility of infection or JRA.  CRP also becomes elevated and returns to normal more rapidly than the ESR. Aspirin has been associated with Reye syndrome in children and adolescents, its use is not recommended for the treatment of fever.

Haemophilus influenzae type B infection  DOC: Oxacillin / Vancomycin  Seldomly seen in children > 5 year old  Usually seen among 3 mos – 5 years.  Neonates are at high risk for infections due to their underdeveloped immune systems. Bacteroides fragilis – most common normal flora in the large intestine; anaerobic Small intestines – gram (-) aerobic Large intestines – gram (-) anaerobic

ANTIBIOTICS FOR MANAGEMENT OF SERIOUSLY ILL CHILDREN WITH FEVER OF UNKNOWN ORIGIN A. Immediate Treatment rd

3 Generation Cephalosporins (Cefotaxime or Ceftriaxone)  provides coverage for both gram (+) and gram (-) organisms  can traverse the blood brain barrier  Given to patients with:  Signs of shock or coma  Meningococcal disease  Age < 1 month  Age 1-3 months and unwell with WBC < 5 or >15 x th 10 to the 9 / L rd th  On the 3 to 4 day, one can differentiate between viral and bacterial cause in WBC count.

B. Treatment for Suspected Bacterial Infection rd

3 Generation Cephalosporins  Given if any of the following are suspected:  Neisseria meningitidis  Streptococcus pnemonia  E. coli  E. coli- most common cause of neonatal sepsis in the Philippines  Pneumococcus sepsis/meningitis Case Fatality Rate is 33% (2010) Staphylococcus aureus infection  DOC: Methicillin  DOC for MRSA: Vancomycin  Community-acquired methicilin resistant Staphylococcus aureus (CA-MRSA) is gaining prevalence, 58% national.

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