INTRODUCTION

Hemophagocytic syndrome (HPS), also known as hemophagocytic lymphohistiocytosis (HLH), is divided into primary and secondary forms. The etiology of secondary HLH is complex; it can be caused by infection, malignant tumors, and autoimmune diseases. Visceral leishmaniasis-related HLH (VLHLH) is very rare in childhood, especially in nonendemic areas. The disease is severe with high mortality rates of up to 100% without early diagnosis and treatment[1,2]. Therefore, the leishmaniasisassociated pathogen must be rapidly and accurately identified for clinical and timely treatment. Here, we report two young patients with VL-HLH diagnosed

bone marrow cell morphology at the Children’s Hospital of Kunming, Yunnan, China in the past 5 years.

The patient continued to have repeated fevers, coughing with sputum, abdominal distension, anorexia, and fatigue. She had a history of mosquito bites and contact with a domestic dog 1 mo before onset as well as a history of Epstein-Barr virus (EBV)-related hemophagocytic syndrome in April 2017.

CASE PRESENTATION

Chief complaints

Repeated irregular fever lasting 3 mo and decreased peripheral blood cells.

支原體肺炎預(yù)后良好，但是肺部陰影的消失比體征消失得慢。極個(gè)別的患兒有可能復(fù)發(fā)，并不是所有的孩子都有可能復(fù)發(fā)。此病只要加強(qiáng)護(hù)理，患兒休息好、多喝水、對(duì)癥用藥即可。支原體肺炎針對(duì)病因治療用藥簡(jiǎn)單，主要使用大環(huán)內(nèi)酯類抗生素治療，其實(shí)不用輸液，口服藥物一樣可以達(dá)到治療的目的，很少出現(xiàn)并發(fā)癥。支原體肺炎不具有傳染性，所以家長(zhǎng)也不用擔(dān)憂。

History of present illness

The patient had recurrent and irregular fever lasting 3 mo and reaching 39–40 °C. After the appearance of fever of symptoms, she was hospitalized at a local hospital for 2 mo. Her blood counts decreased progressively, and she underwent symptomatic and supportive treatment, including meropenem, vancomycin, piperacillin, tazobactam, gamma-globulin, methylprednisolone, cefoperazone, sulbactam, Tienam, and a blood transfusion. The clinical symptoms of the child did not improve, and the child was still feverish. After the above symptomatic treatment, the clinician suspected acute leukemia. She continued to have repeated fevers, coughing with sputum, abdominal distension, anorexia, and fatigue.

The patient had repeated irregular fever lasting for 1 mo and reaching 39–40 °C. Her peripheral blood platelet decreased. She did not recover at her local hospital and was thus transferred to Kunming Children’s Hospital.

另外，還有一些改編自小劇場(chǎng)話劇，這類影片具有實(shí)驗(yàn)性和先鋒性，有著小劇場(chǎng)話劇作為基礎(chǔ)，市場(chǎng)的效果也非常好，比如電影《驢得水》等。

History of past illness

一是課程背景。包括教學(xué)班級(jí)學(xué)期、單元位置、單元目標(biāo)、任務(wù)設(shè)計(jì)、任務(wù)實(shí)施步驟、單元實(shí)施步驟等內(nèi)容。二是教學(xué)步驟。包括引入內(nèi)容、考核任務(wù)及技術(shù)標(biāo)準(zhǔn)、示范任務(wù)、學(xué)練任務(wù)、知識(shí)小結(jié)、單元考核、單元總結(jié)、拓展等內(nèi)容。三是單元設(shè)計(jì)思路。展示單元總情境和子情境的總體設(shè)計(jì)及時(shí)間分配，總結(jié)課程單元設(shè)計(jì)的理念和心得。國(guó)際商法課程可比照上述步驟進(jìn)行課程整體設(shè)計(jì)和單元設(shè)計(jì)。

當(dāng)密碼規(guī)則為類棒圖式，每條線段或折線須經(jīng)過(guò)至少三個(gè)點(diǎn)，且形式為3*3式時(shí)，密碼排列情況共571328種。

None.

Repeated irregular fever for 1 mo and thrombocytopenia found for 2 d.

Physical examination

Both children had long-term irregular fevers, with the highest body temperature exceeding 40 ℃, pancytopenia, and hepatosplenomegaly. Because of these clinical manifestations, they were initially misdiagnosed as having malignant hematological diseases. Neither of them recovered after long-term treatment with drugs at other hospitals, and both had severe infections. VL-HLH is easily misdiagnosed in nonendemic areas because VL manifestations are very similar to those of hematological malignancies. VL symptoms also include a long-term irregular fever, hepatosplenomegaly, and pancytopenia. Additionally, VL has rapid onset and progression. Early symptoms are atypical with many complications; thus, it is easily misdiagnosed[9], especially when combined with EBV infections, leading clinicians to think that it is EBV-associated HLH. Many clinicians have insufficient knowledge and no clinical experience with VL, especially in nonendemic areas. Furthermore, laboratory physicians often lack knowledge of the

Due to the morphology of

amastigotes and platelets is very similar, laboratory physicians may mistake them as platelets; they are also easily engulfed by phagocytes. At the same time, these phagocytes may also contain platelets, red blood cells, and white blood cells, and if the laboratory technicians are unfamiliar with

amastigotes or do not read the results carefully, they may mistake them for platelets. Many reports have found that kala-azar is often misdiagnosed owing to clinicians’ and technicians’ lack of knowledge of

amastigotes[10]. The morphologies of

,

, and histoplasma have many similarities and are easily confused. Clinicians and technicians must be familiar with the morphological characteristics of various pathogens and the differences between them. No

amastigotes were found in either child

bone marrow cell morphology at the previous hospital; thus, the children were misdiagnosed with hematological malignancies. The key to diagnosing these children is to detect the

amastigotes

bone marrow cell morphology combined with their epidemiological histories. To diagnose HLH secondary to kala-azar, finding the pathogen in the bone marrow is the most reliable diagnostic criterion.

Laboratory examinations

Both children were treated with SSG (manufactured by Shandong Xinhua Pharmaceutical Co., Ltd.) at 200 mg antimony/kg. The total amount was divided into six doses, intramuscular injection or intravenous injection twice a week, a course of 3 wk (6 doses). The two patients’ conditions quickly improved.

Visceral leishmaniasis (VL) is caused by

, common pathogens include

, and

, and phlebotomine sandflies are the main transmission vector. The infectious agents of this disease are mainly the patients and sick dogs. The disease is transmitted between humans and animals

blood sucking by phlebotomine sandflies[5-7]. The disease has obvious regional characteristics. VL is scattered throughout six western provinces in China and Xinjiang, Gansu, Sichuan, and Shaanxi[8]. The two cases reported herein were from Weining County, Guizhou, and Yunnan after moving from Zhouqu, Gansu. Both children had lived in epidemic areas and had histories of phlebotomine sandfly bites from June to September (the sandfly breeding season) before disease onset. Weining County in Guizhou and Zhouqu County in Gansu Province are both areas where leishmaniasis was spreading[8]. The epidemiological histories of both children were clear.

總之，“共享經(jīng)濟(jì)”實(shí)質(zhì)上是以盈利為目的的共享，它是人們既擔(dān)任“消費(fèi)者”又充當(dāng)“擁有者”，它把使用權(quán)和所有權(quán)分離，并實(shí)現(xiàn)二者的相互轉(zhuǎn)化，贏得更高的規(guī)模效益。它通過(guò)對(duì)消費(fèi)者需求的分析進(jìn)行資源配置和需求匹配，以最高的精度滿足客戶的需求，同時(shí)發(fā)揮資源自身的價(jià)值?！肮蚕斫?jīng)濟(jì)”平臺(tái)的運(yùn)行是一個(gè)取代了傳統(tǒng)中介機(jī)構(gòu)，基于自身龐大的供給資源和需求客戶實(shí)現(xiàn)再中介化的過(guò)程，它持續(xù)健康發(fā)展的成本收益性也是它利潤(rùn)的最主要來(lái)源。“共享經(jīng)濟(jì)”的運(yùn)行機(jī)制為我國(guó)加快轉(zhuǎn)變經(jīng)濟(jì)發(fā)展方式提供了新的方向和動(dòng)力。

Imaging examinations

Abdominal ultrasound showed enlarged liver and spleen in both children.

在地外天體鉆取采樣探測(cè)領(lǐng)域，目前只有前蘇聯(lián)的Luna24探測(cè)器采用了外部支撐裝置[10]。Luna24探測(cè)器采用滑軌式回轉(zhuǎn)沖擊采樣設(shè)備，該鉆取采樣設(shè)備采用了可拆解式鉆具支撐機(jī)構(gòu)。該機(jī)構(gòu)能夠保證鉆具在探測(cè)器發(fā)射階段至月面著陸階段具有穩(wěn)定支撐，同時(shí)能在鉆機(jī)啟動(dòng)后實(shí)現(xiàn)解鎖動(dòng)作，保障了鉆機(jī)的運(yùn)行空間。Luna24鉆取采樣設(shè)備最終實(shí)現(xiàn)鉆深為2.25 m的鉆取作業(yè)，采集到的月壤樣品的樣芯長(zhǎng)度為1.6 m，質(zhì)量為170 g[11]。

FINAL DIAGNOSIS

Both children were diagnosed with VL-HLH.

TREATMENT

The results of the examination for related pathogens revealed the

amastigotes in the bone marrow of both patients (Figures 1 and 2). Leishmania amastigotes can be seen inside and outside of phagocytes, and their shape was round and oval, with a diameter of about 2 to 5 μm. The cytoplasm was light blue, with a large round nucleus inside, and the nucleus was purplish red. Beside the nucleus, a small, rod-shaped, and darkly colored moving matrix can be seen. The morphological characteristics were consistent with those of

amastigotes. Hemophagocytic cells were easily seen in the bone marrow of both patients (Figure 3). One child was infected with the EBV but tested negative for other pathogens (Table 1).

OUTCOME AND FOLLOW-UP

No

was found in their bone marrow after 3 wk of treatment with the above regimen. Both patients recovered and were discharged.

DISCUSSION

HLH is a life-threatening disease caused by excessive inflammation and multiple organ dysfunction, resulting in uncontrollable lymphocyte and macrophage activation and proliferation[3]. HLH is divided into primary and secondary forms. Infection is the most common cause of secondary HLH[4]. VL-HLH is very rare in childhood and has a high mortality rate if not diagnosed and treated early[1].

The hemoglobin and platelets decreased in both children, and the infection indexes such as highsensitivit C-reactive protein (hs-CRP) and procalcitonin were increased on admission. According to HLH-2004 chemotherapy regimen, after 14 d of treatment, the clinical symptoms and related detection indicators such as routine blood parameters, infection indicators, and other detection items of the two children did not improve. However, the clinical symptoms improved, routine blood parameters, infection indexes, and liver function returned to normal, and no

was found in their bone marrow, after 21 d of sodium stibogluconate (SSG) treatment (Table 2).

Both children had enlarged liver and spleen.

VL-HLH-associated mortality is relatively high. If HLH treatment is ineffective, clinicians should consider whether the HLH is secondary to VL. Both patients in this study underwent 14 d of chemotherapy according to the HLH-2004 chemotherapy regimen, but the chemotherapeutic effect was unsatisfactory, their clinical symptoms did not significantly improve, and their liver and kidney function did not recover as per the related infection indicators. After the disease was clearly diagnosed, they received the recommended treatment, and the disease was quickly controlled. Both patients recovered and were discharged from the hospital. When clinically diagnosing HLH, clinicians should actively search for the cause. If standard treatment for HLH is ineffective, detailed epidemiological histories should be taken, bone marrow cytology examinations should be performed quickly, and HLH secondary to VL should be ruled out.

CONCLUSION

In summary, bone marrow cell morphological examinations play a vital role in diagnosing VL-HLH. When secondary HLH is diagnosed clinically, common pathogens and VL-HLH should both be considered, especially in infants and young children who could not be treated satisfactorily as per the HLH-2004 regimen. Detailed epidemiological histories should be taken, and bone marrow cytology should be re-examined multiple times as soon as possible to find the pathogen and reduce misdiagnoses. Clinicians and technicians should be familiar with the morphological characteristics of

to provide timely and accurate diagnoses.

FOOTNOTES

Shi SL, Zhao H, and Zhou BJ equally contributed to this manuscript; Shi SL and Zhao H wrote the manuscript and carried out the analysis; Ma MB, Li XJ, and Xu J investigated the cases; Zhou BJ and Jiang HC designed and supervised this study; and all authors read and approved the final manuscript.

the Association Foundation Program of Yunnan Science and Technology Department and Kunming Medical University, No. 2019FE001-103; Yunnan Health Training Project of High Level Talents, No. D-2017053; Top Young Experts Training Project for the Academy and Technology in Kunming and Yunnan Province, No. 202005AC160066; Postdoctoral Training Program of Yunnan Province, No. Ynbh19035; and Natural Science Foundation of Yunnan Province, No. 2019-1-C-25318000002240.

Written informed consent was obtained from the patients’ legal guardian for the publication of this case report.

The authors declare no competing interests for this article.

The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).

美伊交惡，殃及在伊中國(guó)油企。本輪美對(duì)伊制裁漾起的沖擊波對(duì)中國(guó)油企影響幾何，油企應(yīng)該如何應(yīng)對(duì)，成為中國(guó)油企需要重視和考慮的問(wèn)題。

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China

Hong-Chao Jiang 0000-0003-3900-1556.

1 Sundar S, Singh OP. Molecular Diagnosis of Visceral Leishmaniasis. Mol Diagn Ther 2018 ; 22 : 443 -457 [PMID:29922885 DOI: 10 .1007 /s40291 -018 -0343 -y]

2 Henter JI, Horne A, Aricó M, Egeler RM, Filipovich AH, Imashuku S, Ladisch S, McClain K, Webb D, Winiarski J, Janka G. HLH-2004 : Diagnostic and therapeutic guidelines for hemophagocytic lymphohistiocytosis. Pediatr Blood Cancer 2007 ;48 : 124 -131 [PMID: 16937360 DOI: 10 .1002 /pbc.21039 ]

3 Janka GE. Familial and acquired hemophagocytic lymphohistiocytosis. Annu Rev Med 2012 ; 63 : 233 -246 [PMID:22248322 DOI: 10 .1146 /annurev-med-041610 -134208 ]

4 Janka G, Imashuku S, Elinder G, Schneider M, Henter JI. Infection- and malignancy-associated hemophagocytic syndromes. Secondary hemophagocytic lymphohistiocytosis.

1998 ; 12 : 435 -444 [PMID:9561911 DOI: 10 .1016 /s0889 -8588 (05 )70521 -9 ]

5 Wang JY, Gao CH, Yang YT, Chen HT, Zhu XH, Lv S, Chen SB, Tong SX, Steinmann P, Ziegelbauer K, Zhou XN. An outbreak of the desert sub-type of zoonotic visceral leishmaniasis in Jiashi, Xinjiang Uygur Autonomous Region, People's Republic of China.

2010 ; 59 : 331 -337 [PMID: 20434585 DOI: 10 .1016 /j.parint.2010 .04 .002 ]

6 Lu HG, Zhong L, Guan LR, Qu JQ, Hu XS, Chai JJ, Xu ZB, Wang CT, Chang KP. Separation of Chinese Leishmania isolates into five genotypes by kinetoplast and chromosomal DNA heterogeneity.

1994 ; 50 : 763 -770[PMID: 8024072 DOI: 10 .4269 /ajtmh.1994 .50 .763 ]

7 Wang JY, Ha Y, Gao CH, Wang Y, Yang YT, Chen HT. The prevalence of canine Leishmania infantum infection in western China detected by PCR and serological tests.

2011 ; 4 : 69 [PMID: 21554677 DOI:10 .1186 /1756 -3305 -4 -69 ]

8 Zheng C, Wang L, Li Y, Zhou XN. Visceral leishmaniasis in northwest China from 2004 to 2018 : a spatio-temporal analysis.

2020 ; 9 : 165 [PMID: 33267898 DOI: 10 .1186 /s40249 -020 -00782 -4 ]

9 Zhao S, Li Z, Zhou S, Zheng C, Ma H. Epidemiological Feature of Visceral Leishmaniasis in China, 2004 -2012 .

2015 ; 44 : 51 -59 [PMID: 26060776 ]

10 Schwing A, Pomares C, Majoor A, Boyer L, Marty P, Michel G. Leishmania infection: Misdiagnosis as cancer and tumorpromoting potential.

2019 ; 197 : 104855 [PMID: 30529443 DOI: 10 .1016 /j.actatropica.2018 .12 .010 ]