Clinical characteristics and prognosis of pediatric cryptococcosis in Beijing Children's Hospital, 2002-2014

Pediatric Cryptococcosis

BACKGROUND

Seroprevalence studies have shown that 70% of children are exposed to Cryptococcus , the most common cause of meningitis in people living with human immunodeficiency virus (HIV), but reported pediatric disease prevalence is much lower than in adults.

METHODS

PubMed and Ovid Global Health databases were searched with the terms "cryptococcosis," "cryptococcal meningitis," " Cryptococcus neoformans " or " Cryptococcus gattii ." All studies reporting pediatric specific data in the English language from 1980 up until December 2022 were included.

RESULTS

One hundred sixty-eight publications were reviewed totaling 1469 children, with the majority reported from Africa (54.2%). Sixty-five percent (961) were HIV positive, 10% (147) were non-HIV immunocompromised and 19% (281) were immunocompetent. Clinical signs and symptoms were only reported for 458 children, with fever (64%), headache (55%) and vomiting (39%) being the most common. Most children (80%) suffered from meningoencephalitis. Lung involvement was rarely described in HIV-positive children (1%), but significantly more common in the non-HIV immunocompromised (36%) and immunocompetent (40%) groups ( P < 0.0001). Only 22% received the recommended antifungal combination therapy, which was significantly higher in immunocompetent children than those with HIV (39% vs. 6.8%; P < 0.0001). Overall mortality was 23%. A significant higher mortality was observed in children with HIV compared with immunocompetent children (32% vs. 16%; P < 0.001), but not compared with children with non-HIV immunosuppression (25).

CONCLUSIONS

This is the largest review of pediatric cryptococcosis with new observations on differences in clinical presentation and outcome depending on the underlying condition. The lack of granular clinical data urges prospective clinical epidemiological studies for improved insight in the epidemiology, management and outcome of cryptococcosis in children.

Cryptococcosis in Southern China: Insights from a Six-Year Retrospective Study in Eastern Guangdong

Objective

Cryptococcosis is a fatal infection that can affect both immunocompetent and immunocompromised patients, and it is little understood in China's various regions. This research aimed to look at the epidemiology, risk factors, and antifungal susceptibility pattern of Cryptococcus neoformans in eastern Guangdong, China.

Methods

A six-year (2016-2022) retrospective study was conducted at Meizhou People's Hospital, China. Demographical, clinical, and laboratory data of cryptococcal patients were collected from hospital records and statistically analyzed using the chi-square and ANOVA tests.

Results

Overall, 170 cryptococcal infections were recorded, of which meningitis accounted for 78 (45.88%), cryptococcemia for 50 (29.41%), and pneumonia for 42 (24.7%). The number of cases increased 8-fold during the study duration. The median age of patients was 58 years (Inter quartile range: 47-66), and the high proportion of cases was from the male population (n = 121, 71.17%). The underlying diseases were identified only in 60 (35.29%) patients, of which 26 (15.29%) were severely immunocompromised, and 26 (15.29%) others were mildly immunocompromised. A statistically significant difference was reported for chronic renal failure, and anemia (p < 0.05) persisted in cases of three infection types. A high number of non-wild type (NWT) isolates were found against amphotericin B (n=13/145, 8.96%), followed by itraconazole (n=7/136, 5.15%) and voriconazole (n=4/158, 2.53%). Only six isolates (3.79%) were multidrug-resistant, four of which were from cryptococcemia patients. Compared to meningitis and pneumonia, cryptococcemia revealed a higher percentage of NWT isolates (p < 0.05).

Conclusion

In high-risk populations, cryptococcal infections require ongoing monitoring and management.

Pulmonary Cryptococcosis

Pulmonary cryptococcosis describes an invasive lung mycosis caused by Cryptococcus neoformans or Cryptococcus gattii complex. It is often a high-consequence disease in both immunocompromised and immunocompetent populations, and may be misdiagnosed as pulmonary malignancy, leading to a delay in therapy. Epidemiology follows that of cryptococcal meningoencephalitis, with C. gattii infection more common in certain geographic regions. Diagnostic tools include histopathology, microscopy and culture, and the detection of cryptococcal polysaccharide antigen or Cryptococcus-derived nucleic acids. All patients with lung cryptococcosis should have a lumbar puncture and cerebral imaging to exclude central nervous system disease. Radiology is key, both as an adjunct to laboratory testing and as the initial means of detection in asymptomatic patients or those with non-specific symptoms. Pulmonary cryptococcomas (single or multiple) may also be associated with disseminated disease and/or cryptococcal meningitis, requiring prolonged treatment regimens. Optimal management for severe disease requires extended induction (amphotericin B and flucytosine) and consolidation therapy (fluconazole) with close clinical monitoring. Susceptibility testing is of value for epidemiology and in regions where relatively high minimum inhibitory concentrations to azoles (particularly fluconazole) have been noted. Novel diagnostic tools and therapeutic agents promise to improve the detection and treatment of cryptococcosis, particularly in low-income settings where the disease burden is high.

Cryptococcal antigen carriage among HIV infected children aged 6 months to 15 years at Laquintinie Hospital in Douala

Background

Up to 15% of deaths of people living with HIV is attributable to meningeal cryptococcosis, with nearly 75% occuring in sub-Saharan Africa. Although rare in children, it is a major cause of morbidity and mortality in people living with HIV. A strong association between cryptococcal antigenemia and the development of meningeal cryptococcosis has been shown in adults. Thus, in 2018, the World Health Organization published an updated version of its guidelines for the diagnosis, prevention and management of cryptococcal infection in adults, adolescents and the HIV-infected child.

Goal

To determine the prevalence of cryptococcal antigenemia and to identify its determinants in children infected with HIV.

Methods

An analytical cross-sectional study was carried out at the approved treatment center of Laquintinie hospital in Douala over a period of 4 months. Children were recruited consecutively after informed parental consent. Cryptococcal antigenemia and CD4 assay were performed using a Cryptops^® immunochromatographic rapid diagnostic test and flow cytometry, respectively. The data collected included the socio-demographic, clinical and paraclinical variables of the children, as well as their antecedents. Data analysis was performed using Epiinfo software version 3.1 and SPSS 21.0. The significance threshold was set at 5%.

Results

A total of 147 children were enrolled. The mean age was 9.8 ± 4.09 years. The majority were on antiretroviral therapy (142, 96.60%). Only 13 (8.80%) were in severe immunosuppression. No child showed signs of meningeal cryptococcosis. The prevalence of cryptococcal antigenemia was 6.12%. Severe immunosuppression [OR: 10.03 (1.52–65.91), p = 0.016] and contact with pigeons [OR: 9.76 (1.14–83.65), p = 0.037] were independent factors significantly associated with the carriage of the cryptococcal antigen.

Conclusion

We recommend screening for cryptococcal antigenemia and routine treatment with fluconazole of all HIV positive children with cryptococcal antigen whether symptomatic or not.

Risk-Based Estimate of Human Fungal Disease Burden, China

We conducted a systematic literature review to obtain risk population–based fungal disease incidence or prevalence data from China. Data were categorized by risk factors and extrapolated by using most recent demographic figures. A total of 71,316,101 cases (5.0% of the population) were attributed to 12 risk factors and 17 fungal diseases. Excluding recurrent Candida vaginitis (4,057/100,000 women) and onychomycosis (2,600/100,000 persons), aspergillosis (317/100,000 persons) was the most common problem; prevalence exceeded that in most other countries. Cryptococcal meningitis, an opportunistic infection, occurs in immunocompetent persons almost twice as often as AIDS. The pattern of fungal infections also varies geographically; Talaromyces marneffei is distributed mainly in the Pearl River Basin, and the Yangtze River bears the greatest histoplasmosis burden. New host populations, new endemic patterns, and high fungal burdens in China, which caused a huge impact on public health, underscore the urgent need for building diagnostic and therapeutic capacity.

Associations between Cryptococcus Genotypes, Phenotypes, and Clinical Parameters of Human Disease: A Review

The genus Cryptococcus contains two primary species complexes that are significant opportunistic human fungal pathogens: C. neoformans and C. gattii. In humans, cryptococcosis can manifest in many ways, but most often results in either pulmonary or central nervous system disease. Patients with cryptococcosis can display a variety of symptoms on a spectrum of severity because of the interaction between yeast and host. The bulk of our knowledge regarding Cryptococcus and the mechanisms of disease stem from in vitro experiments and in vivo animal models that make a fair attempt, but do not recapitulate the conditions inside the human host. To better understand the dynamics of initiation and progression in cryptococcal disease, it is important to study the genetic and phenotypic differences in the context of human infection to identify the human and fungal risk factors that contribute to pathogenesis and poor clinical outcomes. In this review, we summarize the current understanding of the different clinical presentations and health outcomes that are associated with pathogenicity and virulence of cryptococcal strains with respect to specific genotypes and phenotypes.

Cryptococcal infections in children: retrospective study and review from Australia

Aim: Cryptococcosis causes significant morbidity and mortality worldwide, but pediatric data are limited. Methods: A retrospective literature review of Australian pediatric cryptococcosis and additional 10-year audit of cases from a large pediatric network. Results: 22 cases of cryptococcosis in children were identified via literature review: median age was 13.5 years (IQR 7.8-16 years), 18/22 (82%) had meningitis or central nervous system infection. Where outcome was reported, 11/18 (61%) died. Of six audit cases identified from 2008 to 2017, 5 (83%) had C. gattii disease and survived. One child with acute lymphoblastic leukemia and C. neoformans infection died. For survivors, persisting respiratory or neurological sequelae were reported in 4/6 cases (67%). Conclusion: Cryptococcosis is uncommon in Australian children, but is associated with substantial morbidity.

Genotypic diversity and antifungal susceptibility of Cryptococcus neoformans isolates from paediatric patients in China

Cryptococcosis is a life-threatening mycosis primarily occurring in adult patients particularly those with immunosuppression such as HIV infection/AIDS. The number of reported cases of paediatric cryptococcosis has increased in the last decade around the world, including China. However, current information on the characteristics of cryptococcosis in children, particularly the genotypic diversity and antifungal susceptibility of the isolates, is limited. In the present study, a total of 25 paediatric isolates of Cryptococcus neoformans were genotyped using the ISHAM-MLST scheme. In vitro susceptibility to antifungal agents of the 22 isolates was tested using the CLSI M27-A3 method. Our analyses revealed that the genotypic diversity of C. neoformans isolates from Chinese paediatric patients was low, with ST 5 (80%) and ST 31 (12%) being the two major sequence types. Reduced susceptibility to fluconazole (FLU), 5-flucytosine (5-FC) and itraconazole (ITR) was observed among C. neoformans isolates from Chinese paediatric patients, particularly among the ST5 isolates, which was similar to observations made on C. neoformans isolates from Chinese adult patients. In addition, the majority of isolates (3/4, 75%) obtained from deceased patients showed decreased antifungal susceptibility, which indicates that further monitoring of antifungal susceptibility of Cryptococcus isolates is warranted in management of paediatric cryptococcosis.

Systemic cryptococcosis in an immune-competent child

Crytococcus neoformans is an encapsulated yeast that frequently affects immune-compromised patients, although increasingly being detected in the immune-competent host as well. We report a case of disseminated cryptococcosis in a young child in whom no immune deficiency was yet identified. A 4-year-old child presented with high-grade fever, intermittent abdominal pain and generalized skin eruptions for the past two months. He had pallor, firm lymphadenopathy, skin lesions with scarring and firm hepatosplenomegaly. Magnetic resonance imaging of brain and bone-marrow aspiration were normal. Fine-needle-aspiration-cytology of cervical lymph nodes demonstrated Cryptococcus. Serum latex-agglutination test showed a positive titer (1:256). Cryptococcus culture was sterile. The patient received intravenous liposomal amphotericin-B and oral flucytosine for 8 weeks followed by oral fluconazole. Disseminated cryptococcosis with involvement of reticuloendothelial and dermatological systems is rare. Early diagnosis and timely management of associated complications would be life saving.