Exam #3: Diseases of Childhood & Infancy II Flashcards
(43 cards)
What is an ascending infection?
Infection of the neonate via the uterus
What bacteria cause asecnding infection?
E. coli
GBS
What virus causes ascending infection?
HSV II
What are the diseases/ inflammations caused by ascending infection?
1) Chorioamnionitis= inflammation of the fetal membranes (amnion and chorion)
2) Funisitis= inflammation of the connective tissue of the umbilical cord
3) Placentitis
4) Villitis= inflammation of the chorionic villi
What are the consequences of ascending infection?
- Preterm birth
- Recurrent miscarriage
- Fetal Growth Restriction
Describe the microscopic appearance of villitis in perinatal ascending infection.
Remember that this is an inflammation of the chorionic villi & shows LYMPHOCYTIC infiltration of the chorionic villi
What is the difference between early onset & late onset neonatal sepsis?
Early= < 1 week Late= 8 days- 3 months
What pathogens typically cause early onset neonatal spesis? What diseases are these pathogens associated with?
GBS: (meningitis)
Gram negatives:
- E. Coli
- Klebsiella
Note that the gram negative organisms cause pneumonia & meningitis
What pathogens are associated with late-onset neonatal sepsis?
- Staphylococci
- H. influenzae
- Listeria
- Chlamydia
- Mycoplasma
- Candidia
What are the major risk factors for early-onset neonatal sepsis (5)?
1) Previous infant with GBS
2) GBS bacteriuria during pregnancy
3) Delivery before 37 weeks (preterm)= diminished immune system
4) Ruptured membranes (amniotic sac) >18 hours
5) Intrapartum temp >38 C/ 100.4 F
Describe the microscopic appearance of neonatal congenital pneumonia.
Many neutrophils infiltrating immature bronchioles
What are the causes of NRDS (Neonatal Respiratory Distress Syndrome)?
1) Prematurity
2) Lack of surfactant
3) Fetal head injury
4) Sedation
5) Aorta abnormalities
6) Umbilical cord coiling
7) Amniotic fluid aspiration
What is the period for surfactant production in the neonate?
26-32 weeks
Type II pneumocytes
What is hyaline membrane disease?
- This is the most common cause of NRDS i.e. most common specific disease process that causes NRDS, which is due to a lack of surfactant production
- Leading cause of mortality & morbidity in infants
**Hyaline Membrane Disease is characterized by a surfactant deficiency, which leads to alveolar collapse and noncompliant lungs
What are the risk factors for Hyaline Membrane Disease?
1) Preterm
2) Maternal DM
3) C-section
4) Male gender
Outline the pathophysiology of Hyaline Membrane Disease.
N/A
Describe the microscopic appearance of Hyaline Membrane Disease.
Alternating atelectic alveoli & dilated aleolar ducts lined with pink fibrin rich hyaline & necrotic cells
What is the clinical presentation of Hyaline Membrane Disease?
- Respiratory Distress
- Cyanosis
- Hypoxemia
- Hypercarbia
- Metabolic acidosis (mixed)
What are the complications of Hyaline Membrane Disease?
1) Intraventricular hemorrhage
2) PDA
3) Necrotizing enterocolitis
4) Bronchopulmonary dysplasia
5) Retinopathy of prematurity
*****All are associated with hypoxemia & metabolic acidosis
What is Bronchopulmonary Dysplasia?
- Reduced total numbers of alveoli
- Alveolar wall thickening
- Epithelial hyperplasia
- Squamous metaplasia
- Interstitial fibrosis
- Sponge-like radiology
- Predisposition to respiratory infection
All associated with preterm neonates treated with oxygen therapy > 4weeks & positive pressure ventilation
What is post-mortem exterior cobblestone surface of the lung associated with?
This is pathognemonic for Bronchopulmonary Dysplasia
Describe the microscopic appearance of Bronchopulmonary Dysplasia.
- Interstitial fibrosis
- Epithelial hyperplasia
- Squamous metaplasia
- Alveolar wall thickening
What is the clinical presentation of Necrotizing Enterocolitis?
- Abdominal distension
- Ileus
- Bloody stool
*****Note that this can lead to bowel perforation & stricture
Describe the microscopic appearance of Necrotizing Enterocolitis.
- Hemorrhagic necrosis
- Few nuclei
- Villi destruction
- RBC infiltration of all layers of the GI mucosa
**Note that findings will begin in the mucosa & extend into the muscular wall leading to potential perforation
