Childhood histoplasmosis in Colombia: Clinical and laboratory observations of 45 patients

Overview of invasive fungal infections in children in South America - the threat of resistant Candida species and the role of climate change in the new geographic distribution of endemic systemic mycosis

PURPOSE OF REVIEW

Invasive fungal infection (IFI) in children is a growing problem with crescent morbidity and mortality, well recognized in developed countries, affecting mainly immunocompromised children, including neonates and children in intensive care units. The burden of IFI in South American children is less well comprehended. In addition, the current epidemiology of endemic systemic mycoses in children may have changed over time.

RECENT FINDINGS

Candida spp. infections are very prevalent in South America hospitalized children, especially in neonates, in a rate far superior compared to developed countries. C. auris, has already been responsible for outbreaks in neonates and children in Venezuela and Colombia. Sporotrichosis is well established as an urban zoonosis in impoverish families. Paracoccidioidomycosis and histoplasmosis are affecting new areas of Brazil, probably due to climate change, deforestation, and human migration.

SUMMARY

This review aims to unveil the real dimension of these infections in South American children. Hopefully, the awareness brought by this review will help healthcare professionals to recognize IFI more easily and it will provide support for getting more resources for IFI treatment and prevention.

Histoplasmosis in African children: clinical features, diagnosis and treatment

Most of the reviews on histoplasmosis documented in literature have been in the adult population. Very few studies highlight the peculiarities associated with histoplasmosis in Africa especially in the pediatric population. This review addresses the above concerns with clinical summaries and diagnosis of some case reports of histoplasmosis in African children. We highlighted 44 case reports of histoplasmosis in African children (1950–2021) distributed across Western Africa (38.6%, n = 17), Eastern Africa (9.1%, n = 4), Southern Africa (9.1%, n = 4), and Central Africa (43.2%, n = 19). No case report was found from Northern Africa. The age range was 1–17 years, with a mean of 9.2. Of the 44 case reports, 8 cases (18.2%, 8/44) were caused by Histoplasma capsulatum var capsulatum, 33 cases (75%, 33/44) were caused by Histoplasma capsulatum var duboisii, and specie identification was not found in 3 cases. Only three (6.8%) cases were HIV positive; 56.8% (25/44) were disseminated histoplasmosis, pulmonary histoplasmosis accounted for just one case (2.3%, 1/44). Extrapulmonary presentation included skin lesions (ulcers, fistulas, nodules, patches, pigmentations, papules, and abscesses), bone lesions, osteoarthritis, and fractures. The commonest sites affected were skin ( n = 29, 65.9%), bones ( n = 20, 45.5%), and lymph nodes ( n = 15, 34.1%). Histopathology was the commonest diagnostic method ( n = 33, 75%). Amphotericin B was first-line therapy in 45.5% of the cases ( n = 20) followed by ketoconazole (20.5%, n = 9); 27 cases (61.4%) had favorable outcomes, 8 cases (18.2%) had fatal outcomes, while in 9 cases, the outcome was not revealed. This review revealed several cases of histoplasmosis misdiagnosed as other conditions including tuberculosis ( n = 3, 6.8%), pneumonia ( n = 1, 2.3%), cancers ( n = 4, 9.1%), nephritic syndrome ( n = 1, 2.3%), leishmaniasis ( n = 1, 2.3%), and hyperreactive malarial splenomegaly syndrome ( n = 1, 2.3%). In addition, histoplasmosis was not considered in some case reports even when symptoms were suggestive. Diagnosis of histoplasmosis was made at autopsy with postmortem findings suggestive of histoplasmosis ( n = 3, 6.8%). This report highlights the need for a paradigm shift on the part of pediatricians in Africa. They need to look beyond clinical conditions considered common in our environment for this age group and evaluate for other diseases including histoplasmosis.

Invasive Fungal Infections in Under-Five Diarrheal Children: Experience from an Urban Diarrheal Disease Hospital

Invasive fungal infections (IFIs) are opportunistic, especially in immunocompromised and hospitalized patients. Children with IFIs are more vulnerable to a fatal outcome. For early diagnosis and treatment, knowledge of the spectrum and frequency of IFIs among children is prerequisite. In this prospective observational study, we enrolled 168 children of 2–59 months old of either sex from March 2018 to December 2019 admitted to the Dhaka hospital, icddr,b. Study participants with suspected IFIs were with or without severe acute malnutrition (SAM) along with sepsis/pneumonia and fulfilled any of the following criteria: (i) failure to respond to injectable antibiotics, (ii) development of a late-onset hospital-acquired infection, (iii) needed ICU care for >7 days, (iv) took steroids/antibiotics for >2 weeks before hospitalization, and (v) developed thrush after taking injectable antibiotics. The comparison group included non-SAM (weight-for-length Z score ≥ −2) children with diarrhea and fever <3 days in the absence of co-morbidity. We performed real-time PCR, ELISA, and blood culture for the detection of fungal pathogen. Study group children with SAM, positive ELISA and PCR considered to have a IFIs. In the study group, 15/138 (10.87%) children had IFIs. Among IFIs, invasive candidiasis, aspergillosis, histoplasmosis detected in 6 (4.53%), 11 (7.97%), and 1 (0.72%) children, respectively, and (3/15 [2.17%]) children had both candidiasis and aspergillosis. Children with IFIs more often encountered septic shock (26.7% vs. 4.9%; p = 0.013) and had a higher death rate (46.7% vs. 8.9%; p < 0.001) than those without IFIs. IFIs were independently associated with female sex (OR = 3.48; 95% CI = 1.05, 11.55; p = 0.042) after adjusting for potential confounders. Our findings thus implicate that, malnourished children with septic shock require targeted screening for the early diagnosis and prompt management of IFIs that may help to reduce IFIs related deaths.

Histoplasmosis in Children; HIV/AIDS Not a Major Driver

The classification of histoplasmosis as an AIDS-defining illness has largely attributed its occurrence in people to the presence of HIV/AIDS especially in Africa. Prior to the advent of the HIV/AIDS epidemic, several cases of histoplasmosis were documented both in the pediatric and adult populations. Our review revealed 1461 reported cases of pediatric histoplasmosis globally in the last eight decades (1939-2021). North America (n = 1231) had the highest number of cases, followed by South America (n = 135), Africa (n = 65), Asia (n = 26) and Europe (n = 4). Histoplasmosis was much more common in the non-HIV pediatric population (n = 1418, 97.1%) compared to the HIV population. The non-HIV factors implicated were, childhood malignancies (n = 207), such as leukemias and lymphomas as well as their treatment, lung diseases (n = 7), environmental exposures and toxins (n = 224), autoimmune diseases (n = 12), organ transplants (n = 12), long-term steroid therapy (n = 3), the use of immunosuppressive drugs such as TNF-alpha inhibitors (n = 7) malnutrition (n = 12), histiocytosis (n = 3), Hyper immunoglobulin M and E syndromes (n = 15, 1.2%), pancytopenia (n = 26), diabetes mellitus (n = 1) and T-cell deficiency (n = 21). Paediatricians should always consider or rule out a diagnosis of histoplasmosis in children presenting with symptoms suggestive of the above clinical conditions.

Paediatric Histoplasmosis 2000-2019: A Review of 83 Cases

Histoplasmosis is an endemic fungal infection that is confined to specific geographical regions. Histoplasma spp. are primary pathogens that cause disease in both immunocompetent and immunocompromised patients, ranging from a single-organ (mostly affecting the lungs) infection to life-threatening disseminated disease. Knowledge about the clinical epidemiology relies on data from adult populations; little is known about the patient and disease characteristics in the paediatric population. Therefore, a structured review of published cases of paediatric histoplasmosis between 2000 and 2019 was performed. A literature search of PubMed was conducted and the epidemiological and clinical data from 83 cases were analysed. The mean age at presentation was 9.5 ± 5.5 years, and 51% were girls. Two-thirds of the children were immunocompromised. The majority of children presented with disseminated disease. The most frequently observed clinical symptoms were respiratory symptoms, alongside non-specific systemic features, including fever, myalgia, fatigue and weight loss. The mortality rate was 11%. Histoplasmosis affects children of any age. Being immunocompromised is a risk factor for severe and disseminated disease. The lack of specific presenting features leads to underreporting and delay in diagnosis. To improve the recognition and outcome of histoplasmosis in childhood, increased awareness and surveillance systems are warranted.

Histoplasmosis in the Republic of Congo dominated by African histoplasmosis, Histoplasma capsulatum var. duboisii

The Republic of Congo (RoC) is one of the African countries with the most histoplasmosis cases reported. This review summarizes the current status regarding epidemiology, diagnostic tools, and treatment of histoplasmosis in the RoC. A computerized search was performed from online databases Medline, PubMed, HINARI, and Google Scholar to collect literature on histoplasmosis in the RoC. We found 57 cases of histoplasmosis diagnosed between 1954 and 2019, corresponding to an incidence rate of 1-3 cases each year without significant impact of the AIDS epidemic in the country. Of the 57 cases, 54 (94.7%) were cases of Histoplasma capsulatum var. duboisii (Hcd) infection, African histoplasmosis. Three cases (5.3%) of Histoplasma capsulatum var. capsulatum infection were recorded, but all were acquired outside in the RoC. The patients' ages ranged between 13 months to 60 years. An equal number of cases were observed in adults in the third or fourth decades (n = 14; 24.6%) and in children aged ≤15 years. Skin lesions (46.3%), lymph nodes (37%), and bone lesions (26%) were the most frequent clinical presentations. Most diagnoses were based on histopathology and distinctive large yeast forms seen in tissue. Amphotericin B (AmB) was first line therapy in 65% of the cases and itraconazole (25%) for maintenance therapy. The occurrence of African histoplasmosis in apparently normal children raises the possibility that African histoplasmosis is linked to environmental fungal exposure.

A comparison of presentations and outcomes of histoplasmosis across patients with varying immune status

Few large cohorts have examined histoplasmosis in both immunocompromised and immunocompetent patients. We describe the differences in presentations and outcomes of histoplasmosis by immune and dissemination status. We assembled a retrospective cohort of adult patients diagnosed with histoplasmosis from 2002 to 2017. Patients were grouped by immune status: people living with HIV (PLWH), patients who were HIV negative but had other-immunocompromise (OIC), and immunocompetent patients. Patients were further classified into asymptomatic lung nodule (ALN), localized and disseminated disease groups, and outcomes were compared across patients by these immune status categories We identified 261 patients with histoplasmosis: 54 (21%) PLWH, 98 (38%) OIC, and 109 (42%) immunocompetent. Disseminated disease was more common among PLWH than among other groups (P < .001). In localized disease, median time from symptom onset to diagnosis was longer in immunocompetent patients than in other groups (P = .012), and was not significant in disseminated disease. The 90-day mortality was higher in PLWH (25%) and OIC (26%) with localized disease compared to the immunocompetent group (4%) (P = .009), but this difference was not seen in disseminated disease. Patients with localized disease had lower 90-day mortality (14%) compared to those with disseminated disease (21%) (P = .034). We conclude that immunocompetent individuals present with fewer typical symptoms, laboratory findings, and radiographic features of Histoplasma infection, leading to potential delays in diagnosis in this group. Despite this, immunocompetent patients have lower 90-day mortality in localized disease, and do not experience increased 90-day mortality in disseminated disease.

LAY SUMMARY

This article examines how the signs and symptoms of histoplasmosis vary by immune status and dissemination status. Immunocompetent patients with localized disease present with fewer typical signs and symptoms, are diagnosed later, but despite this have lower 90-day mortality.

[Histoplasmosis in Argentina: case series in children]

BACKGROUND

Histoplasmosis is a fungal disease, endemic in South America, and seldom reported in paediatrics.

AIMS

To report the epidemiology, clinical features and outcome of children diagnosed with histoplasmosis in an Argentinian Children's Hospital.

METHODS

A retrospective and descriptive study was performed from January 2008 to December 2016 in Hospital de Pediatría 'Prof. Dr. Juan Pedro Garrahan'. Patients under 18 years with clinical features, serological tests, cultures and/or histological findings compatible with histoplasmosis were included. Thirteen patients were selected (seven male and six female; mean age was 9 years with interquartile range 3.4-13); three children (23%) were from Buenos Aires province, three (23%) from Santa Fe province, and seven (54%) from other provinces.

RESULTS

In ten cases (77%) the clinical form was disseminated, and it was pulmonary in three (23%). Eight cases (62%) suffered other comorbidities. Serological tests were positive in seven patients (54%), with positive cultures obtained in nine patients (69%). Histological findings compatible with histoplasmosis were found in 10 cases (77%). All patients received treatment with amphotericin B (liposomal formulation in seven cases, deoxycholate in six), with 10 patients continuing with oral itraconazole. Three patients (23%) died from causes unrelated to histoplasmosis.

CONCLUSIONS

The majority of children in the series had comorbidities and disseminated histoplasmosis. Mortality was not directly associated with histoplasmosis.

Pediatric Histoplasmosis in an Area of Endemicity: A Contemporary Analysis

BACKGROUND

Data on pediatric histoplasmosis have been limited to those from outbreak and case reports. We sought to evaluate the contemporary clinical manifestations, laboratory findings, and outcomes in children with histoplasmosis living in an area of endemicity.

METHODS

This study was a single-center retrospective review of proven and probable cases of histoplasmosis in children aged 0 to 18 years between April 2008 and April 2014. Case ascertainment was ensured by us using International Classification of Diseases, Ninth Revision codes cross-referenced with laboratory, microbiology, and histopathology tests that detected Histoplasma capsulatum. Demographics, diagnostics, clinical management, and outcomes were evaluated.

RESULTS

Seventy-three children with histoplasmosis (41 males; median age, 13 years [range, 3-18 years]) were diagnosed with proven (n = 17 [23%]) or probable (n = 56 [77%]) histoplasmosis, which manifested as pulmonary (n = 52 [71%]) or disseminated (n = 21 [29%]) disease. Symptoms at presentation were nonspecific; the examination of 21 (29%) patients revealed abnormal physical findings. Detection of H capsulatum by serologic methods occurred in 93% (63 of 68) of the patients tested. Histoplasma antigen in blood or urine was detected in 42% (20 of 48) and 28% (15 of 53) of the patients tested, respectively. The 16 (22%) patients who were immunocompromised had significantly higher rates of disseminated disease (56% vs 21%, respectively; P = .01), antigenuria (62% vs 18%, respectively; P = .004), and antigenemia (69% vs 31%, respectively; P = .02) and longer durations of antigenuria (403 vs 120 days, respectively; P = .003) and antigenemia (451 vs 149 days, respectively; P < .0001) than did the immunocompetent children.

CONCLUSIONS

Pediatric histoplasmosis manifests most frequently as pulmonary disease. The highest diagnostic yield was achieved when multiple diagnostic modalities were used. Presentation with disseminated disease and evidence of antigenemia, antigenuria, and delayed antigen clearance were more likely to be seen in immunocompromised children.

Endemic Mycoses in Children

The endemic mycoses are a group of infections caused by fungi with a distinct geographic distribution, defined by climatic and environmental conditions. The systemic endemic mycoses, namely histoplasmosis, blastomycosis, talaromycosis, coccidioidomycosis and paracoccidioidomycosis, occur after the inhalation of fungal spores. The cutaneous endemic mycoses, including sporotrichosis, mycetoma, entomophthoramycosis and chromoblastomycosis, enter the host via traumatic inoculation of the skin. Clinical presentation varies between these relatively heterogeneous infections, as does the susceptibility of immunosuppressed patients to disease. An understanding of the geographic range, typical manifestations, diagnostic methods, and treatment of the endemic mycoses is key in assessing patients presenting with atypical infections who may have traveled to endemic areas.