Paediatrics Marrow Pg 81-90 (Childhood Infections)

Late Onset Torch Infections

• Hutchinson's Triad: Syphilis infection after 2 years of age, characterized by Sensorineural Hearing Loss (SNHL), Interstitial Keratitis, and Hutchinson's Teeth.
• Mulberry Molars: Irregular surface of molars with rudimentary cups, typically affecting the first molar.
• Deformed Nose: Saddle nose deformity precedes notching of incisors, peg-shaped incisors, perforations, and deformed nose caused by bony deformities.
• Rhagodes: Fissures around the mouth and nose.
• Saber Shin: Bowing of the tibia.
• Clutton's Joint: Bilateral knee effusion caused by Syphilis.

Management of Torch Infections

• Diagnosis: VDRL (Venereal Disease Research Laboratory) test for both baby and mother.
• Diagnostic Criteria: A four-fold increase in VDRL titres confirms a diagnosis of Syphilis.
• Treatment: Aqueous crystalline penicillin or Penicillin G is the preferred treatment, followed by 3rd generation cephalosporins such as Ceftriaxone.

Congenital Zika Virus Infection

• Transmission: Occurs through the Aedes aegypti mosquito.
• Period of Risk: The first trimester of pregnancy.
• Transmission: Infected mothers transmit the virus to their unborn babies.

Congenital Zika Virus Infection: Skull Manifestations

• Skull Abnormalities: Partial collapse of the skull and internal abnormalities like overlapping of sutures.
• Brain Damage: Microcephaly, Hypertonia/Spasticity, and Extrapyramidal manifestations including choreoathetosis.
• Other Features: Damage to the basal ganglia and occipital prominence.

Erythema Infectiosum (Fifth Disease)

• Etiology: Parvovirus B19 (single-stranded DNA virus).
• Incubation Period: 4 to 28 days.
• Age Group: Primarily affects children over 5 years old

Erythema Infectiosum: Clinical Features

• Prodromal Stage: Fever lasting for 1-2 days.
• Exanthematous Phase: Slapped-cheek appearance facial flushing (Stage 1), followed by diffuse macular erythema spreading to the trunk and extremities (Stage 2). The rash then develops central clearing giving a lacy/reticulated appearance (Stage 3).

Erythema Infectiosum: Associations

• Arthralgia: Affects older children.
• Transient Aplastic Crisis: Occurs in individuals with pre-existing hemolytic anemia and parvovirus B19 infection. Presents with pancytopenia.
• Infection in the Mother (During Pregnancy): Associated with fetal hydrops and fetal death.

Erythema Infectiosum: Complications

• Post-Infectious Thrombocytopenia (PRP): Develops 2-3 weeks after infection and is usually self-limiting.
• Arthritis: Common in older children.
• Progressive Rubella Panencephalitis (PRP): Most severe complication, presents with features similar to subacute sclerosing panencephalitis (SSPE).

Erythema Infectiosum: Management

• Good Prognosis: Supportive management with good prognosis.

Congenital Varicella Syndrome (Congenital Chickenpox)

• Transmission: Intrauterine transmission of varicella zoster virus.
• Period of Risk: Occurs during the third trimester (13 to 20 weeks of gestation), with the highest risk period being 5 days before to 2 days after delivery.
• Clinical Features: Cerebral atrophy, Microcephaly, Limb hypoplasia, and scarring (irregular scarring similar to burn scars).
• Management: IV immunoglobulin (Ig) is administered immediately after birth for prevention, and acyclovir is given if lesions are present.

Congenital Syphilis (Congenital Treponema Pallidum Infection)

• Unique Feature: Recurrent abortion.
• Period of Risk: Greater than 4 months of gestation (2nd and 3rd trimesters).
• Clinical Features:
  • Early Onset (< 2 years): Rhinitis (Snuffles) is the first feature, followed by bone metaphysis, osteochondritis, and periostitis.
  • Severe Syphilis: Bone pain and edema of affected limb, pseudo paralysis.
  • Vesiculobullous rash seen in palms and soles.
  • Pemphigus syphiliticus (blistering rash).

Roseola Infantum (Exanthema Subitum, Sixth Disease)

• Etiology: Human herpes virus (HHV) 6 and 7, and echovirus 16.
• Age Group: Affects children between 6 months and 3 years old.
• Clinical Features:
  • Prodromal Stage (1-4 days): Fever, Cough, and Running nose.
  • Exanthematous Phase (On day 4): Maculopapular rash starting in the trunk, fever intensity decreases after the rash appears, no residual pigmentation.
  • Exanthem: Nagayama spots (erythematous macules in the soft palate and uvula) can be observed.

Roseola Infantum: Treatment and Prognosis

• Treatment: Supportive care.
• Prognosis: Good prognosis.

Hand, Foot, and Mouth Disease (HFMD)

• Age Group: Preschoolers (< 5 years old).
• Causative Agent: Coxsackie A16 and Enterovirus 71.
• Mode of Spread: Direct contact or through infected fomites (e.g., used towels).
• Clinical Features: Fever, Vesicles that resolve within 4-5 days.
• Treatment: Supportive care.
• Common Complication: Temporary loss of nails 4 weeks after initial infection.

Varicella (Chickenpox)

• Causative Agent: Varicella-zoster virus (double-stranded DNA virus).
• Incubation Period: 10-21 days.
• Mode of Spread: Droplet spread.
• Infective Period: 24-48 hours before the onset of the rash.
• Secondary Attack Rate: 80%.

Varicella: Clinical Features

• Fever: Fever on day 2, lasting for 3-5 days.
• Rash: Macule to papule to vesicle (classical rash) that is pruritic and starts in the trunk, spreading to other areas. Leaves behind hypo/hyperpigmented macules. Pleomorphic appearance ("dew drop on a rose petal" appearance).

Varicella: Complications

• Secondary Bacterial Infection of Skin Lesion: Staphylococcus aureus and Streptococcus pyogenes.
• Neurological: Cerebellar ataxia, meningo-encephalitis.
• Reye's Syndrome: Associated with aspirin usage during varicella infection.
• Hepatic Encephalopathy.

Varicella: Diagnosis

• Primarily clinical.
• Tzanck Smear: Lesion is scrapped and examined microscopically, revealing multinucleated giant cells, but this method has poor sensitivity.
• Serology: Anti-IgM antibodies against varicella.

Varicella: Treatment

• Antipyretics: Paracetamol.
• Antiviral: Acyclovir (20 mg/kg/dose x 4 times/day). Start within 48 hours of onset. Ibuprofen should be avoided due to an increased risk of necrotizing fasciitis.

Varicella: Prevention

• Varicella Vaccine: Live attenuated Oka strain. Two doses are given subcutaneously. The first dose is administered at 15-18 months of age and the second dose at 4-6 years of age.
• Post-Exposure Prophylaxis (VZIG): For high-risk contacts, including:
  • Immunocompromised children.
  • Pregnant women.
  • Neonate born to a mother who was affected (5 days before to 2 days after delivery).

TORCH Infections

• Transmitted intrauterine infections from mother to baby.
• Includes: Toxoplasmosis, Other (Syphilis, Zika virus, Parvo B19 virus), Rubella, Cytomegalovirus (CMV), Herpes simplex.

General Aspects of TORCH Infections

• Primary Infection: The mother is infected during pregnancy, leading to mother-to-child transmission.
• Time of Gestation: First trimester infections are most common due to increased risk of congenital anomalies and the highest risk of transmission.

General Aspects of TORCH Infections (Continued)

• Secondary/Reactivation: Latent infection reactivation in the mother during pregnancy.
• Transmission: Transmission of syphilis and CMV.

Common Manifestations of TORCH Infections

• Antenatal: Intrauterine growth restriction (IUGR) is the most common, followed by Intrauterine death (IUD), preterm delivery, and abortions.

Congenital Rubella Syndrome (CRS)

• Severe maturation infection.

Congenital Rubella Syndrome: Clinical Manifestations

• Clinical Triad:
  • Heart Defects: Patent ductus arteriosus (PDA), Pulmonary artery stenosis (PS), Ventricular septal defect (VSD).
  • Sensorineural hearing loss (SNHL) (most common).
  • Cataract.

Congenital Rubella Syndrome: Postnatal Manifestations

• Bone Marrow Suppression: Anemia, thrombocytopenia.
• Hepatosplenomegaly.
• Lymphadenopathy.
• Jaundice or abnormal Liver function Tests (LFTs).

Other features of Congenital Rubella Syndrome

• Salt and Pepper Retinopathy: Black and white spots on the retina, the most common ocular finding.
• Blueberry Muffin Lesion: Purpuric, non-blanching, dome-shaped papules, found in severe CRS. Represents dermal erythropoiesis.
• Non-Specific: Also seen in other intrauterine infections.

Congenital Rubella Syndrome: Chronic Manifestations

• Progressive Rubella Panencephalitis (PRP): Onset during school going age, features similar to subacute sclerosing panencephalitis (SSPE), poor scholastic performance, seizures, and intellectual impairment.
• Adult-Onset Diabetes.
• Hypothyroidism.

Congenital Rubella Syndrome: Diagnosis

• Histology: Fetal IgM antibodies against rubella (Maternal IgM cannot cross the placenta).
• IgG: Not used because maternal IgG can cross the placenta.

Congenital Rubella Syndrome: Management

• No Treatment: Damage is permanent.
• Prevention: Immunization of parents during their childhood.

Congenital Cytomegalovirus (CMV) Infection

• Most common TORCH infection.
• Transmission Rate:
  • Third Trimester (90%): Organogenesis is complete, often asymptomatic.
  • First Trimester: Organogenesis is incomplete, leading to Congenital Cytomegalic Inclusion Disease.

Congenital CMV: Limb Manifestations

• Small head size (microcephaly).
• Vision and Hearing problems.
• Problems moving limbs and body.
• Brain damage.
• Seizures.
• Problems with feeding (difficulty swallowing).

Congenital CMV: Arthrogryposis Multiplex Congenita

• Coloboma (a gap or split in a normally rounded structure).
• Pigmentary retinal mottling (spots or flecks of pigment on the retina).
• Scarring in the macula of the eye.

Congenital Parvovirus B19 Infection

• Transmission: Across all trimesters of pregnancy.
• Most Sensitive Period: Second trimester.
• Tropism for erythroid lineage: Primarily affecting the pronormoblast stage.

Congenital Parvovirus B19 Infection: Clinical Features

• Severe anemia: Leads to high-output cardiac failure.

Congenital Parvovirus B19 Infection: Diagram of Transmission

• Flowchart depicts the transmission of parvovirus B19 from the bone marrow to the liver, and then to the heart, ultimately resulting in fetal hydrops.

Congenital Parvovirus B19 Infection: Direct Cytopathic effects on the Myocardium

• Myocarditis.
• Fetal cardiac arrest.
• Intrauterine death (IUD).

Post-Streptococcal Complications

• Acute rheumatic fever.
• Post-streptococcal glomerulonephritis (PSGN).
• Post-streptococcal reactive arthritis.

Post-Streptococcal Complications: Management

• Investigations: Throat swab.
• Treatment: Oral penicillin V for 10 days or Amoxicillin for 10 days.

Rubella (German Measles, 3-Day Measles)

• Etiology: Togaviridae (single-stranded RNA virus).
• Incubation Period: 14-21 days.
• Mode of Spread: Respiratory droplets.
• Infectivity period: 5 days before to 6 days after onset of rash.

Rubella: Clinical features

• Rash: The first and most prominent sign, appearing on day 1 without a prodromal stage. Maculopapular rash starts behind the ear/face, spreading downwards. Does not cause desquamation or discoloration after it fades.
• Exanthem:
  - Forchheimer spots: Tiny, rose-colored lesions in the oropharynx. - Lymphadenopathy: Involving suboccipital, posterior auricular, and anterior cervical lymph nodes.

Rubella: Clinical Features: (continued)

• Pastia's lines: accentuation of the rash at skin creases.

TORCH Infections: Rubella Clinical Features

-  Triad:  
   -  Microcephaly. 
    -  Chorioretinitis. 
    -  Intracranial calcification.

 -  Other Features:
    -  Sensorineural Hearing Loss (SNHL): Most common long-term sequelae, the most common cause of non-syndromic hearing loss in children.
    -  Rash: Petechiae (due to low platelets), Blueberry muffin lesion, and can also be seen in other intrauterine infections.

TORCH Infections: Rubella Diagnosis

    -  PCR testing: Urine sample is preferred over blood or saliva. Performed as early as possible for screening.
    -  Serology: IgM antibodies against CMV (Low sensitivity).

TORCH Infections: Rubella Treatment

   -  Ganciclovir:  IV for 6 weeks, followed by oral administration for 6 months. Prevents progression of neurological disorders and reduces the risk of SNHL. 

TORCH Infections: Congenital Toxoplasmosis

• Transmission Risk: Highest in the third trimester.
• Clinical Features:
• Triad: Hydrocephalus (unique to toxoplasmosis), Chorioretinitis, and Intracranial calcification.

TORCH Infections: Congenital Toxoplasmosis Diagnosis

• Serology:
  • IgM/IgA ELISA (more sensitive)
  • Immunosorbent agglutination assay (ISAGA) test.
  • PCR in CSF/tissue sample (if neurological involvement is present).

TORCH Infections: Congenital Toxoplasmosis Treatment

• Treatment: All cases, both symptomatic and asymptomatic, should be treated.
• Pyrimethamine + Sulfadiazine for 1 year, along with folinic acid to prevent bone marrow suppression caused by the medication.

TORCH Infections: Congenital Toxoplasmosis Other Manifestations

• Low IQ.
• Deafness (SNHL).
• Microcephaly in some cases.