Purpura in a 5 year old girlBMJ 2017; 357 doi: https://doi.org/10.1136/bmj.j2530 (Published 15 June 2017) Cite this as: BMJ 2017;357:j2530
- 1Department of paediatrics, Hsinchu Mackay Memorial Hospital, Hsinchu City, Taiwan
- 2Division of infection and pathway medicine, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK
- Correspondence to C-Yu Lin,
A 5 year old girl presented with a one day history of fever, coryzal symptoms, and multiple skin lesions. She also reported abdominal pain and had vomited once. Physical examination revealed hypotension and multiple petechial bruises and purpura-like lesions over the four limbs and the face (fig 1⇓). Over 12 hours, the skin lesions evolved into irregular gangrenous purpura with a central dusky necrosis surrounded by fading redness (fig 2⇓). Blood tests revealed anaemia, thrombocytopenia, high C reactive protein, acute renal failure, and coagulopathy.
What is the most likely diagnosis?
How would you manage the most likely diagnosis?
What are the preventive measures?
1. What is the most likely diagnosis?
Purpura fulminans caused by Neisseria meningitidis.
Purpura fulminans refers to a rapidly progressive thrombotic disorder that manifests with disseminated intravascular coagulation, intravascular thrombosis, and haemorrhagic infarction of the skin.1 It can herald multiple organ failure and has a high mortality rate (10%~ >50%).2 The disease course is fulminant, and early recognition of purpura fulminans is crucial for successful treatment.2 The initial skin lesions can manifest as well demarcated erythematous macules that progress to irregular blue-black haemorrhagic necrotic areas. Within hours, occlusion of the small vessels with microthrombi can lead to the lesions progressing to full-thickness skin necrosis or extensive soft tissue necrosis.3 Early manifestations of purpura fulminans can be confused with simple traumatic wounds or with other purpuric lesions, such as Henoch Schonlein purpura, thrombotic thrombocytopenic purpura, and immune thrombocytopenic purpura. A definite diagnosis can be established based on the rapid sequential changes.
Usually, purpura fulminans is caused by disseminated Neisseria meningitidis infection. It occurs in 10%–20% of patients with meningococcal septicemia.4 The incidence of meningococcal infection varies according to the geographical location and the patient’s age: the incidence in the United States is between 6 and 7 cases per 100 000 population in infants, and can be as high as 1 in 1000 total population in the “meningitis belt” in sub-Saharan Africa.56 Isolation of causative microbes is the gold standard of diagnosis, which permits antibiotic susceptibility testing. A simple blood smear could provide pre-emptive diagnosis to guide antimicrobial treatment. The blood culture of the patient reported here yielded a Gram negative diplococcus, which was ultimately identified as a meningococcus (fig 3⇓). Molecular techniques to detect meningococcus are rapid and accurate but not readily available in many areas.1 Occasionally, other severe infections can cause purpura fulminans, such as Streptococcus pneumoniae, Group A and B streptococci, Haemophilus influenzae, Staphylococcus aureus, and varicella.1 Rarely, purpura fulminans occurs in patients with protein C and protein S deficiency.1 Prompt diagnosis is essential for a successful treatment.
2. How would you manage the most likely diagnosis?
Immediate broad spectrum antimicrobial treatment, supportive care in an intensive care environment, and correction of the coagulopathy.
Purpura fulminans is a medical emergency because of the rapid progression of disseminated intravascular coagulation and the possibility of multiple organ failure.7 The UK joint specialist societies guideline recommends treatment with third generation cephalosporins.8 Even with prompt antibiotic use, the fatality rate is high (10%-50%).2457 Patients should be managed in the intensive care unit with respiratory and circulatory care, treatment of multiple organ failure, and correction of coagulopathy.9 An intensive care and multidisciplinary collaboration are warranted in treating meningococcal disease.189
3. What are the preventive measures?
Initiate chemoprophylaxis of close contacts and vaccination groups who are at risk.
While treating the patient with purpura fulminans, chemoprophylaxis is recommended by the Centers for Disease Control and Prevention for close contacts, including healthcare workers, as soon as possible after exposure.5 In close contacts of a patient with purpura fulminans, the risk of contracting meningococcal disease is reported to be ~500-800 times greater than in the general population. Regimens for chemoprophylaxis include rifampin, ciprofloxacin, and ceftriaxone. Monotherapy with ciprofloxacin or rifampicin is the preferred therapy and antimicrobial susceptibility should be taken into consideration.58 Vaccination against meningococcus is another important preventive measure, and is recommended for individuals at risk, such as inpatients with persistent complement component deficiencies, anatomic or functional asplenia, travellers to endemic areas, and people who have been in contact with the disease.5 There are at least 12 capsular groups based on the capsular polysaccharide, and five capsular groups of N meningitidis (A, B, C, W, and Y) that are responsible for most meningococcal diseases in children and adults. Currently, there are several licensed or developing vaccines for meningococcus, including quadrivalent conjugate vaccines (against capsular groups A, C, W, and Y; MenACWY-D, Menactra, MenACWY-TT, Nimenrix, and MenACWY-CRM, Menveo), bivalent conjugate vaccine (against groups C and Y; Hib-MenCY-TT, MenHibrix), quadrivalent polysaccharide vaccine (against groups A, C, W, and Y; MPSV4, Menomune), and monovalent vaccines (against group A, B, or C; group B: MenB-FHbp, Trumenba, and MenB-4C, Bexsero).510 Vaccination protection is usually group specific and there are concerns about waning effectiveness over time.510 Policies for meningococcal vaccination vary by country according to the local rates of meningococcal disease, prevalent capsular groups, available resources, and evaluation of vaccine effectiveness and cost effectiveness. For example, the incidence of invasive meningococcal disease is highly prevalent in the meningitis belt of Sub-Saharan Africa where capsular group A meningococcus causes both endemic and epidemic disease. There have been efforts to control these epidemics with the introduction of the conjugate meningococcal A vaccine.5
After prompt supportive care, blood transfusion, antimicrobial treatment, and continuous venovenous haemofiltration, the patient underwent an uneventful recovery. The necrotic skin lesions healed, and no skin grafting was required. In Taiwan, capsular group B is the most common cause of meningococcal meningitis, but meningococcal vaccination is not included in the national immunisation programme at present.
Parental consent obtained.