Category Archives: Infectious disease

Monkeypox

General paediatrics, Infectious disease

=mpox (considered less stigmatising?).

Emerging infection particularly in men who have sex with men. Reached the UK in 2022.

New variant (Clade I) has high mortality, started in Central Africa (Congo, Central African Republic, Burundi, Uganda), now in Kenya, first case now reported in Europe (Sweden, 2024). Grade 3 human pathogen (along with Yersinia pestis, O157, TB, anthrax…).

Viral haemorrhagic fever found in these areas too, of course…

Incubation period is 5-21 days. High risk would be household contact, mucosal (with bodily fluids) or broken skin, inhalation without PPE if cleaning room or changing bedding. Medium risk would be intact skin with bodily fluids or face to face within 1m considered medium risk – do not need to isolate but should be offered post-exposure prophylaxis. See PHS matrix.

Besides blistering rash, can cause fever, sore throat, lymphadenopathy, myalgia.

Swab blistering lesion, or if none then throat. MSS (molecular sampling solution, as used for flu etc) ideally otherwise extra transport precautions required. Mark sample “suspected HCID”, notify lab in advance – needs to arrive for 9am!!!

Cases are asked to self isolate at home.

PPE – as for viral haemorrhagic fever. https://learn.nes.nhs.scot/58193/high-consequence-infectious-diseases-hcid

Post-exposure prophylaxis with MVA-BN vaccine (Imvanex®) offered within 14 days. Pregnant and children under 5 considered at risk.

Smallpox vaccine was considered effective.

Pyrexia of Unknown Origin

Clinical, General paediatrics, Immunology, Infectious disease

A technical term, not just a fever without obvious source! Essentially presence of confirmed fever for 8 days or more in a child in whom a careful thorough history and physical examination, and preliminary laboratory data fail to reveal a probable cause.

Long list of possible causes, long lists of possible tests – do thorough history and repeated examinations, then follow the clues!

In kids, infection is the commonest cause. But can be connective tissue disorder, or malignancy.

Beware factitious fever – admission sensible.

If possible, stop all drugs. Antipyretics may obscure the pattern of fever, and can occasionally be its cause (drug fever is one cause).

Unless the child is critically ill, try not to give antibiotics. If the diagnosis remains obscure, go back and take the history again, examine the child (fully) again, send the specimens again!

Special points in history/examination

  • Travel – malaria can present 6-12 months later. Typhoid.
  • Ethnicity – tuberculosis
  • Outdoor activities – rats/ticks as vectors of infectious diseases
  • Animal contact – cows/sheep (brucellosis), cats (cat scratch)
  • Mouth ulcers (IBD, Behcets, PFAPA)
  • Periodicity – see Periodic fever
  • Sinus tenderness, nasal congestion (sinusitis)
  • Bone/spine tenderness – discitis, vertebral osteomyelitis

Tests

  • 3 sets of blood cultures, different sites, different times (at least a few hours apart), off antibiotics – standard for endocarditis
  • ASOT
  • EBV, CMV
  • LDH, CK
  • ANA/RF
  • Urine/stool culture
  • Swab everything!
[Rosie Hague, Current peds 2001]

PFAPA

General paediatrics, Immunology, Infectious disease

=periodic fever, aphthous stomatitis, pharyngitis, adenitis.

Fever every 4-6 weeks (periodic). Neutrophil count normal, cf cyclical neutropenia.

Besides mouth ulcers, sore throat and cervical lymphadenopathy, headache, musty smell (!), abdo pain.

Affected children continue to grow normally, are well between attacks, and do not suffer long-term sequelae.

Treatment with steroids or with cimetidine has been effective, and some children have had no further attacks following tonsillectomy (which suggests some relationship with strep infection but not clear).

Periodic fever

General paediatrics, Immunology, Infectious disease
Infectious causes
Mycobacteria (TB and non-tuberculous disease)
Borrelia
Leptospira
Streptobacillus moniliformis (rat bite fever)
Hepatitis B
Orbivirus
Rickettsea (typhus)
Entamoeba histolytica
Others
Cyclical neutropoenia
PFAPA
Behcet’s
Hyper IgD (HIDS)
Familial Mediterranean fever
Familial Hibernian fever/TRAPS
Cryopyrin disorder

Periodic fevers are defined as uniform periods of fever that recur regularly in individuals who are healthy between attacks. Parents may organize life eg holidays around expected attacks and don’t have any concerns otherwise cf child with recurrent respiratory and gastrointestinal infections after starting nursery who “always has something”.

Recurrent bacterial infections esp recurrent/chronic pneumonia or otitis media may indicate a humoral immune defect. Similarly, recurrent documented viral or fungal infections may indicate a cell mediated immune defect.

Tick borne encephalitis

General paediatrics, Infectious disease

Arbovirus, spread by ticks, big problem in forested regions of Europe and vaccine available.

In Scotland, “Louping ill” is tick born encephalitis affecting sheep – v rarely humans too.

Since 2019, 3 cases of TBE in England (virus had been found in ticks in Southern England before), and recently 1 in Scotland. Patient had a dozen or so ticks that were only removed after a day.

Lyme disease is the other important tick borne infection.

Orbital cellulitis

General paediatrics, Infectious disease, Surgical

Potentially serious infection of the eye.

Chandler classification describes the potential sequence of events:

  • Preseptal (periorbital) cellulitis, in other words, anterior to the eye. Usually caused by skin organisms entering via superficial trauma
  • Orbital cellulitis – surrounding the eye
  • Subperiosteal orbital abscess – penetration into bone of orbit
  • Orbital abscess
  • Cavernous sinus thrombosis

In older children, more likely to start with sinusitis, then eroding through into orbit. Differentiating between these types is difficult without imaging.

Different organisms cf skin commensals of preseptal cellulitis eg Haemophilus, streptococci including pneumococcus, anaerobes.

Often no organism is obtained, which adds to the difficulty of giving evidence based guidance. Multiple bugs not uncommon. Hence a variety of different guidelines, generally of poor quality.

In a large US review of 220 children and young adults, 98% were investigated by CT. High rate of steroid use – previous studies have suggested better outcomes, but no obvious benefit in terms of treatment success here. Various antibiotic regimens, various durations. More treatment failures if treated for more than 3 weeks but these will be the most severe/complex cases.

Management

Jointly managed by ophthalmology, ENT and paediatrics. Ophthalmology are best at performing eye movement assessment, but it is ENT who tend to do any surgery (usually endoscopic sinus surgery).

Red flags:

  • Severe proptosis,
  • worsening visual acuity,
  • elevated intraocular pressure,
  • colour indiscrimination,
  • intracranial involvement,
  • inability to perform a reliable serial ophthalmologic examination,
  • poor response to a trial of intravenous antibiotics for 24 to 48 hours

These are indications for surgery.

The size of any subperiosteal abscess on CT is a new prognostic factor: diameter >10mm and volumes ≥500mm3 (although volume measurements not routinely reported) are thought typically to require immediate surgical intervention, with the remainder going to surgery only in the event of clinical deterioration, lack of clinical improvement after 48 hours of antibiotics, or worsening abscess on imaging.

Treatment duration – most people would agree to IV treatment until clear improvement, followed by oral antibiotics for a total of 14 days.

Long COVID

General paediatrics, Infectious disease, Mental health, OPD, Psychology

Doesn’t seem to be associated with severity of initial illness.

Long COVID is less common if you are vaccinated already. In a community based study of adults aged 18 to 69 years infected with SARS-CoV-2 before vaccination against covid-19, the odds of experiencing long covid symptoms decreased by an average of 13% after a first covid-19 vaccine dose, with a further 9% decrease in the odds of long covid after a second dose. [https://doi.org/10.1136/bmj-2021-069676] 

If you already have long COVID, further COVID immunisations seem to be beneficial, rather than harmful:

  • In a non-controlled study of 900 social media users with long COVID, more than half experienced an improvement in symptoms after vaccination compared with 7% who reported a deterioration.19
  • A study of 44 vaccinated patients and 22 unvaccinated controls previously admitted to hospital with covid-19 in the UK, which inevitably had limited power to detect clinically relevant effects, found no evidence for vaccination being associated with worsening of long covid symptoms or quality of life.20
  • A French study of 455 self-selected participants found reduced long COVID symptom burden and double the rate of remission at 120 days in vaccinated participants compared with unvaccinated controls.

All about symptoms, excluding treatable conditions, then self management. For adults:

https://www.yourcovidrecovery.nhs.uk/

Threadworms

Common, General paediatrics, Infectious disease, OPD

=enterobius. Common in young children, probably due to hygiene issues. Also called pinworms. Small (1-2cm), like white threads. Can be intensely itchy, usually in night when worms emerge to lay eggs.

Mebendazole effective at killing live worms in gut, not effective if eggs in vagina. Licensed from age 2 but can be used off license below that. Does not kill eggs however, and main issue is reinfection so consider treating whole family, with repeat doses after 2 weeks when any eggs will have hatched. NHS Inform advice on hygiene:

  • Lifespan of threadworms is approximately 6 weeks, so follow hygiene measures for at least this length of time.
  • Everyone in the household must follow the advice outlined below.
  • Wash all night clothes, bed linen, towels and soft toys (normal temperatures OK but make sure the washing is well rinsed [presumably at start of treatment; dilution more important than soap?]
  • Vacuum and dust the whole house esp bedrooms – repeat regularly
  • Clean bathroom and kitchen surfaces – again, rinse cloth frequently – repeat regularly
  • Avoid shaking out clothes/bedding that may be contaminated with eggs, to prevent eggs being transferred to other surfaces
  • Don’t eat food in the bedroom
  • Keep fingernails short
  • Discourage nail-biting and sucking fingers/thumbs
  • Wash hands frequently and scrub under your fingernails esp before eating, after going to the toilet, and before and after changing your baby’s nappy
  • wear close-fitting underwear at night and change your underwear every morning
  • bathe or shower regularly – it’s particularly important to bathe or shower first thing in the morning: make sure you clean around your anus and vagina to remove any eggs
  • don’t share towels
  • keep toothbrushes in a closed cupboard and rinse them thoroughly before use!

Eggs probably become unviable after a few days if not in warm and moist environment… Children may of course pick up another threadworm infection from school/nursery…

Sometimes you just have to keep repeating treatment over months/years! Mebendazole is harmless (v little systemic absorption), although symptoms may be caused by clearance of large worm burdens.