Brain Abscess in Children

A brain abscess is a localized infection. Most often, it's called a bacterial infection. 

Risk Factors For Brain Abscess

Twenty percent of cases had no risk factor.  Septic Contiguous Focus: The primary risk factor for children. It is able to propagate via located Another name for pyogenic meningitis is acute pyogenic meningitis. Mastoiditis with otitis media, Thrombosis in the cavernous sinus, Cellulitis orbitale, Sinus inflammation, Dental abscess, Immunosuppression: Both common and uncommon bacteria, such as those found in fungus abscesses, can cause this deep-Setting Accidents.

After Following Surgery

Pulmonary arteriovenous malformations (PAVMs) and Tetralogy of Fallot (TOF) are two examples of right-to-left shunts. VP Shunt is an example of foreign material in the central nervous system.

Also Read: Neonatal Seizures- Etiology, Clinical Features And Management

Location & Pathology  

 In 82% of cases, just one brain lesion is discovered; in 18% of cases, numerous lesions are discovered. In youngsters, it is most frequently detected in the left and right lobes of the brain. The frontal, parietal, and temporal lobes of the cerebral cortex will experience 80% of the abscess.  15%–20% in the brainstem, cerebellum, and occipital lobe 

Adults are more likely to develop abscesses on the left side of the brain than the right. This is owing to the fact that penetrating injuries are the most frequent mechanism and that homicidal or fist cuff-related injuries frequently result in penetrating injuries. 

 In children, the frontal lobe is generally the site of brain abscesses the most frequently. Parietal lobe is the most often affected area in patients with TOF. The most frequently found region in patients with CSOM/mastoiditis is the temporal lobe. 

Also Read: High-Yield Image Based Questions On Neonatology

Stages Of Brain Abscess

Bacteria that penetrate the brain cause an abscess in the comparatively avascular areas. Two common patterns of bacterial invasion are as follows:  Contiguous Dispersion-Spread hemogenously: embedded in the avascular region. Grey-white matter junction, for instance.

4 Stages

• First Stage: There are no particular symptoms and the illness might last up to three to five days.
• Stage 2: Late celebrities might linger for four to nine days.
• Third stage: Ten to fourteen days after the cereberitis starts, early fibrotic capsule development occurs.
• Stage 4: After 15 days, late capsule development takes place.
There will be a lot of cerebral edema in the latter two stages. When diagnosing celebrities, MRI is incredibly sensitive. 

Etiology  

One pathogen is anaerobic and typically the result of a mucosal lesion in ⅓ of the patients, who were determined to be monomicrobial. ⅓ of the patients have polymicrobial infections. 

Streptococci, specifically the Streptococcus anginosus group (S. anginosus, S. intermedius, and S. constellatus), are the most prevalent bacterium in 33% of cases. Staph aureus is the cause of 11% of infections. Commonly observed in piercing wounds. 

Other

• Pneumococci
• Viridans strep.
• Anaerobes
• Enterococci
• G-ve

Neonatal Brain Abscess

• Citrobacter
• Cronobacter
• Serratia
• Proteus mirabilis
• Listeria
• Immunosupperesion:  Fungi (aspergillus), parasites

Also Read: Retinopathy of Prematurity- Mechanism and Treatment

Clinical Features

Early: Low-grade fever, headache, fatigue, and varying degrees of irritation. The frontal lobe's involvement will result in altered sensorium and personality alterations. Headaches became more frequent after seizures.  Papilledema, vomiting, and cranial nerve symptoms due to elevated ICP.  Specific neurodeficits, such as hemiparesis. 

Shock and death can result from an abscess rupture into the brain's interventricular system (27-85%). Frontal lobe abscess associated with mild or late raised ICP but early personality alterations. Ataxia (I/L): vomiting, nystagmus, and dysmetria (occurs due to an abscess in the occipital lobe).

Also Read: Non-Immune Hydrops-Etiology, Investigations And Treatment

Investigation  

When examining a brain abscess, MRI brain with contrast is the preferred method of inquiry. A T2 weighted sample with surrounding edema will exhibit an enhanced signal intensity. A CT scan is less accurate. In the event that this center has a parenchymal low density area and a ring-enhancing lesion. 

Positive Investigations: EEG focal slowing, TLC elevation, and 20–30% positive blood cultures. Although lumbar punctures are generally avoided, >50% of instances result in pleocytosis and protein. 

Treatment

The preferred course of treatment is six weeks of empirical IV antibiotic therapy. Vancomycin plus/or ceftriaxone plus/or metronidazole.
Vancomycin + Meropenem is an alternate treatment option if you suspect G-negative bacteria or polymicrobacteria. If there is a suspicion of Listeria infection, use Ampicillin + Gentamicin (+/- 3rd gen. cephalosporin) and Amphoterecin B if there is a possible fungal abscess.

Role Of Surgery  

Large (>2.5 cm), superficial, non-resolving abscess is an indication for surgery. (After four to six weeks, a follow-up MRI)  Bacteria that form gas. Unconfirmed fungal abscess: straightforward guided aspiration

Avoid Surgery
Five or more abscesses. A deep abscess that is near important structures.

Prognosis

Death rate: 5 to 10%. Consequences: Hemiparesis, cranial nerve palsies, behavioral issues, seizures, and epilepsies.

Poor Prognosis

If an abscess develops in a child under a year old. A postponed start of antibiotics.  Abscesses fungi.  Several Abscesses. 

Also Read: Hearing Loss in Nicu Graduates

Hope you found this blog helpful for your NEET SS Pediatrics Neurology Preparation. For more informative and interesting posts like these, keep reading PrepLadder’s blogs.